|  UNITED STATESSECURITIES AND EXCHANGE COMMISSIONWashington, D.C. 20549 FORM 10-Q QUARTERLY REPORT PURSUANT TO SECTION 13 OR 15(d) OF THESECURITIES EXCHANGE ACT OF 1934 For the quarterly period ended MARCH 31, 2010 Commission file number: 1-1463 UNION CARBIDE CORPORATION(Exact name of registrant as specified in its charter)                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                       |
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| New York(State or other jurisdiction of     incorporation or organization)                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                | 13-1421730(I.R.S. Employer Identification No.) |
|  1254 Enclave Parkway, Houston, Texas  77077(Address of principal executive offices)          (Zip Code)                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                          |
|  Registrant's telephone number, including area code:  281-966-2727                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  |
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| Indicate by check mark whether the registrant (1) has filed all reports required to be filed by Section 13 or 15(d) of the Securities Exchange Act of 1934 during the preceding 12 months (or for such shorter period that the registrant was required to file such reports), and (2) has been subject to such filing requirements for the past 90 days.       þ Yes    o No                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      |
| Indicate by check mark whether the registrant has submitted electronically and posted on its corporate Web site, if any, every Interactive Data File required to be submitted and posted pursuant to Rule 405 of Regulation S-T (§232.405 of this chapter) during the preceding 12 months (or for such shorter period that the registrant was required to submit and post such files).                                                                                                                                                                                                                                                        o Yes    o No  |
| Indicate by check mark whether the registrant is a large accelerated filer, an accelerated filer, a non-accelerated filer or a smaller reporting company. See definitions of “large accelerated filer,” “accelerated filer” and “smaller reporting company” in Rule 12b-2 of the Exchange Act.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                            |
| Large accelerated filer o                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                          | Accelerated filer o |
| Non-accelerated filer   þ                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                      | Smaller reporting company o |
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| Indicate by check mark whether the registrant is a shell company (as defined in Rule 12b-2 of the Exchange Act).o Yes    þ No                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                             |
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| At March 31, 2010, 1,000 shares of common stock were outstanding, all of which were held by the registrant’s parent, The Dow Chemical Company. The registrant meets the conditions set forth in General Instructions H(1)(a) and (b) for Form 10-Q and is therefore filing this form with a reduced disclosure format.                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                  |

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TABLE OF CONTENTS

|                                                                                                            | PAGE     |
|-----------------------------------------------------------------------------------------------------------------|----------|
| PART I - FINANCIAL INFORMATION                                                                                  |     |
|  Item 1.  Financial Statements.                                                                  |  3  |
|  Consolidated Statements of Income                                                                         |  3  |
|  Consolidated Balance Sheets                                                                               |  4  |
|  Consolidated Statements of Cash Flows                                                                     |  5  |
|  Consolidated Statements of Equity                                                                         |  6  |
|  Consolidated Statements of Comprehensive Income                                                           |  6  |
|  Notes to the Consolidated Financial Statements                                                            |  7  |
|  Item 2.  Management's Discussion and Analysis of Financial Condition and Results of Operations. |  17 |
|  Disclosure Regarding Forward-Looking Information                                                          |  17 |
|  Results of Operations                                                                                     |  17 |
|  Other Matters                                                                                             |  18 |
|  Item 3.  Quantitative and Qualitative Disclosures About Market Risk.                            |  21 |
|  Item 4.  Controls and Procedures.                                                               | 21       |
|  PART II - OTHER INFORMATION                                                                               |     |
|  Item 1.  Legal Proceedings.                                                                     |  22 |
|  Item 1A.  Risk Factors.                                                                         |  22 |
|  Item 6.  Exhibits.                                                                              |  22 |
|  SIGNATURES                                                                                                |  23 |
|  EXHIBIT INDEX                                                                                             |  24 |

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Table of Contents

| PART I - FINANCIAL INFORMATION                       |   |               |   |      |   |   |
|------------------------------------------------------|--------|--------------------|--------|-----------|--------|--------|
|                                                 |   |               |   |      |   |   |
| ITEM 1. Financial Statements.                        |   |               |   |      |   |   |
|                                                 |   |               |   |      |   |   |
| Union Carbide Corporation and Subsidiaries           |
| Consolidated Statements of Income                    |
|                                                 |   |               |   |      |   |   |
|                                                 |   | Three Months Ended |
|                                                 |   | March 31,          |   | March 31, |
| In millions     (Unaudited) |   | 2010               |   | 2009      |
| Net trade sales                                      |   | $                  | 48     |      |   | $      | 35 |   |
| Net sales to related companies                       |   |               | 1,556  |      |   |   | 1,003 |   |
| Total Net Sales                                      |   |               | 1,604  |      |   |   | 1,038 |   |
| Cost of sales                                        |   |               | 1,563  |      |   |   | 1,019 |   |
| Research and development expenses                    |   |               | 11     |      |   |   | 14 |   |
| Selling, general and administrative expenses         |   |               | 3      |      |   |   | 3 |   |
| Restructuring charges                                |   |               | 5      |      |   |   | 4 |   |
| Equity in earnings of nonconsolidated affiliates     |   |               | 9      |      |   |   | 2 |   |
| Sundry income (expense) - net                        |   |               | 6      |      |   |   | (3 | ) |
| Interest income                                      |   |               | 18     |      |   |   | 6 |   |
| Interest expense and amortization of debt discount   |   |               | 10     |      |   |   | 14 |   |
| Income (Loss) before Income Taxes                    |   |               | 45     |      |   |   | (11 | ) |
| Credit for income taxes                              |   |               | (17    | )         |   |   | (38 | ) |
| Net Income Attributable to Union Carbide Corporation |   | $                  | 62     |      |   | $      | 27 |   |
|                                                 |   |               |   |      |   |   |   |   |
|                                                 |   |               |   |      |   |   |   |   |
|                                                 |   |               |   |      |   |   |   |   |
| Depreciation                                         |   | $                  | 63     |      |   | $      | 68 |   |
| Capital Expenditures                                 |   | $                  | 18     |      |   | $      | 21 |   |
| See Notes to the Consolidated Financial Statements.  |   |               |   |      |   |   |   |   |

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| Union Carbide Corporation and Subsidiaries                                                           |
|------------------------------------------------------------------------------------------------------|
| Consolidated Balance Sheets                                                                          |
|                                                                                                 |   |   |   |   |   |   |
|                                                                                                 |   | March 31, |   |   | Dec. 31, |   |
| In millions     (Unaudited)                                                 |   | 2010 |   |   | 2009 |   |
| Assets                                                                                               |   |   |   |   |   |   |
| Current Assets                                                                                       |   |   |   |   |   |   |
| Cash and cash equivalents                                                                            |   | $ | 16 |   |   | $ | 22 |   |
| Accounts receivable:                                                                                 |   |   |   |   |   |   |   |   |
|      Trade (net of allowance for doubtful receivables - 2010: $1; 2009: $1) |   |   | 23 |   |   |   | 20 |   |
|      Related companies                                                      |   |   | 440 |   |   |   | 371 |   |
|      Other                                                                  |   |   | 227 |   |   |   | 254 |   |
| Notes receivable from related companies                                                              |   |   | 4,260 |   |   |   | 4,150 |   |
| Inventories                                                                                          |   |   | 195 |   |   |   | 207 |   |
| Other current assets and deferred income taxes                                                       |   |   | 69 |   |   |   | 109 |   |
| Total current assets                                                                                 |   |   | 5,230 |   |   |   | 5,133 |   |
| Investments                                                                                          |   |   |   |   |   |   |   |   |
| Investments in related companies                                                                     |   |   | 972 |   |   |   | 972 |   |
| Investments in nonconsolidated affiliates                                                            |   |   | 117 |   |   |   | 116 |   |
| Other investments                                                                                    |   |   | 24 |   |   |   | 21 |   |
| Noncurrent receivables                                                                               |   |   | 47 |   |   |   | 47 |   |
| Noncurrent receivables from related companies                                                        |   |   | 120 |   |   |   | 101 |   |
| Total investments                                                                                    |   |   | 1,280 |   |   |   | 1,257 |   |
| Property                                                                                             |   |   |   |   |   |   |   |   |
| Property                                                                                             |   |   | 7,281 |   |   |   | 7,533 |   |
| Less accumulated depreciation                                                                        |   |   | 5,789 |   |   |   | 5,986 |   |
| Net property                                                                                         |   |   | 1,492 |   |   |   | 1,547 |   |
| Other Assets                                                                                         |   |   |   |   |   |   |   |   |
| Other intangible assets (net of accumulated amortization 2010: $137; 2009: $140)                     |   |   | 9 |   |   |   | 10 |   |
| Deferred income tax assets - noncurrent                                                              |   |   | 511 |   |   |   | 498 |   |
| Asbestos-related insurance receivables - noncurrent                                                  |   |   | 313 |   |   |   | 330 |   |
| Deferred charges and other assets                                                                    |   |   | 73 |   |   |   | 73 |   |
| Total other assets                                                                                   |   |   | 906 |   |   |   | 911 |   |
| Total Assets                                                                                         |   | $ | 8,908 |   |   | $ | 8,848 |   |
| Liabilities and Equity                                                                               |   |   |   |   |   |   |   |   |
| Current Liabilities                                                                                  |   |   |   |   |   |   |   |   |
| Notes payable - related companies                                                                    |   | $ | 3 |   |   | $ | 3 |   |
| Accounts payable:                                                                                    |   |   |   |   |   |   |   |   |
|      Trade                                                                  |   |   | 227 |   |   |   | 225 |   |
|      Related companies                                                      |   |   | 517 |   |   |   | 329 |   |
|      Other                                                                  |   |   | 25 |   |   |   | 28 |   |
| Income taxes payable                                                                                 |   |   | 129 |   |   |   | 119 |   |
| Asbestos-related liabilities - current                                                               |   |   | 110 |   |   |   | 115 |   |
| Accrued and other current liabilities                                                                |   |   | 201 |   |   |   | 195 |   |
| Total current liabilities                                                                            |   |   | 1,212 |   |   |   | 1,014 |   |
| Long-Term Debt                                                                                       |   |   | 571 |   |   |   | 571 |   |
| Other Noncurrent Liabilities                                                                         |   |   |   |   |   |   |   |   |
| Pension and other postretirement benefits - noncurrent                                               |   |   | 842 |   |   |   | 855 |   |
| Asbestos-related liabilities - noncurrent                                                            |   |   | 727 |   |   |   | 734 |   |
| Other noncurrent obligations                                                                         |   |   | 198 |   |   |   | 240 |   |
| Total other noncurrent liabilities                                                                   |   |   | 1,767 |   |   |   | 1,829 |   |
| Stockholder's Equity                                                                                 |   |   |   |   |   |   |   |   |
| Common stock (authorized and issued: 1,000 shares of $0.01 par value each)                           |   |   | - |   |   |   | - |   |
| Additional paid-in capital                                                                           |   |   | 312 |   |   |   | 312 |   |
| Retained earnings                                                                                    |   |   | 6,043 |   |   |   | 6,131 |   |
| Accumulated other comprehensive loss                                                                 |   |   | (999 | ) |   |   | (1,010 | ) |
| Union Carbide Corporation's stockholder's equity                                                     |   |   | 5,356 |   |   |   | 5,433 |   |
| Noncontrolling interests                                                                             |   |   | 2 |   |   |   | 1 |   |
| Total equity                                                                                         |   |   | 5,358 |   |   |   | 5,434 |   |
| Total Liabilities and Equity                                                                         |   | $ | 8,908 |   |   | $ | 8,848 |   |
| See Notes to the Consolidated Financial Statements.                                                  |   |   |   |   |   |   |   |   |

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Table of Contents

| Union Carbide Corporation and Subsidiaries                                                                                                     |
|------------------------------------------------------------------------------------------------------------------------------------------------|
| Consolidated Statements of Cash Flows                                                                                                          |
|                                                                                                                                           |   | Three Months Ended |
|                                                                                                                                           |   | March 31, |   | March 31, |
| In millions     (Unaudited)                                                                                           |   | 2010 |   | 2009 |
| Operating Activities                                                                                                                           |   |   |   |   |   |   |
| Net Income                                                                                                                                     |   | $ | 62 |   |   | $ | 27 |   |
| Adjustments to reconcile net income to net cash provided by operating activities:                                                              |   |   |   |   |   |   |   |   |
|           Depreciation and amortization                                                      |   |   | 69 |   |   |   | 75 |   |
|           Provision (credit) for deferred income tax                                         |   |   | 14 |   |   |   | (8 | ) |
|           Earnings of nonconsolidated affiliates in excess of (less than) dividends received |   |   | (1 | ) |   |   | 16 |   |
|           Restructuring charges                                                              |   |   | 5 |   |   |   | 4 |   |
|           Pension contributions                                                              |   |   | - |   |   |   | (1 | ) |
| Changes in assets and liabilities:                                                                                                             |   |   |   |   |   |   |   |   |
|           Accounts and notes receivable                                                      |   |   | (16 | ) |   |   | - |   |
|           Related company receivables                                                        |   |   | (179 | ) |   |   | 149 |   |
|           Inventories                                                                        |   |   | 12 |   |   |   | (3 | ) |
|           Accounts payable                                                                   |   |   | 13 |   |   |   | 23 |   |
|           Related company payables                                                           |   |   | 188 |   |   |   | (107 | ) |
|           Other assets and liabilities                                                       |   |   | 14 |   |   |   | (134 | ) |
| Cash provided by operating activities                                                                                                          |   |   | 181 |   |   |   | 41 |   |
| Investing Activities                                                                                                                           |   |   |   |   |   |   |   |   |
| Capital expenditures                                                                                                                           |   |   | (18 | ) |   |   | (21 | ) |
| Change in noncurrent receivable from related company                                                                                           |   |   | (19 | ) |   |   | (24 | ) |
| Purchases of investments                                                                                                                       |   |   | (8 | ) |   |   | (8 | ) |
| Proceeds from sales of investments                                                                                                             |   |   | 8 |   |   |   | 8 |   |
| Cash used in investing activities                                                                                                              |   |   | (37 | ) |   |   | (45 | ) |
| Financing Activities                                                                                                                           |   |   |   |   |   |   |   |   |
| Dividends paid to stockholder                                                                                                                  |   |   | (150 | ) |   |   | - |   |
| Cash used in financing activities                                                                                                              |   |   | (150 | ) |   |   | - |   |
| Summary                                                                                                                                        |   |   |   |   |   |   |   |   |
| Decrease in cash and cash equivalents                                                                                                          |   |   | (6 | ) |   |   | (4 | ) |
| Cash and cash equivalents at beginning of year                                                                                                 |   |   | 22 |   |   |   | 24 |   |
| Cash and cash equivalents at end of period                                                                                                     |   | $ | 16 |   |   | $ | 20 |   |
| See Notes to the Consolidated Financial Statements.                                                                                            |   |   |   |   |   |   |   |   |

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| Union Carbide Corporation and Subsidiaries                          |
|---------------------------------------------------------------------|
| Consolidated Statements of Equity                                   |
|                                                                |   | Three Months Ended |
|                                                                |   | March 31, |   | March 31, |
| In millions     (Unaudited)                |   | 2010 |   | 2009 |
| Common Stock                                                        |   |   |   |   |   |   |
| Balance at beginning of year and end of period                      |   |   | - |   |   |   | - |   |
| Additional Paid-in Capital                                          |   |   |   |   |   |   |   |   |
| Balance at beginning of year and end of period                      |   | $ | 312 |   |   | $ | 312 |   |
| Retained Earnings                                                   |   |   |   |   |   |   |   |   |
| Balance at beginning of year                                        |   |   | 6,131 |   |   |   | 6,094 |   |
| Net income                                                          |   |   | 62 |   |   |   | 27 |   |
| Dividend declared                                                   |   |   | (150 | ) |   |   | - |   |
| Other                                                               |   |   | - |   |   |   | 1 |   |
| Balance at end of period                                            |   |   | 6,043 |   |   |   | 6,122 |   |
| Accumulated Other Comprehensive Loss, Net of Tax                    |   |   |   |   |   |   |   |   |
| Cumulative Translation Adjustments at beginning of year             |   |   | (61 | ) |   |   | (61 | ) |
| Translation adjustments                                             |   |   | - |   |   |   | (5 | ) |
| Balance at end of period                                            |   |   | (61 | ) |   |   | (66 | ) |
| Pension and Other Postretirement Benefit Plans at beginning of year |   |   | (950 | ) |   |   | (783 | ) |
| Net gain (loss)                                                     |   |   | 11 |   |   |   | (2 | ) |
| Pension and Other Postretirement Benefit Plans at end of period     |   |   | (939 | ) |   |   | (785 | ) |
| Accumulated Investment Gain at beginning of year                    |   |   | 1 |   |   |   | 1 |   |
| Net investment results                                              |   |   | - |   |   |   | (1 | ) |
| Balance at end of period                                            |   |   | 1 |   |   |   | - |   |
| Accumulated Derivative Loss at beginning of year and end of period  |   |   | - |   |   |   | (1 | ) |
| Total accumulated other comprehensive loss                          |   |   | (999 | ) |   |   | (852 | ) |
| Union Carbide Corporation's Stockholder's Equity                    |   |   | 5,356 |   |   |   | 5,582 |   |
| Noncontrolling Interests                                            |   |   | 2 |   |   |   | 1 |   |
| Total Equity                                                        |   | $ | 5,358 |   |   | $ | 5,583 |   |
| See Notes to the Consolidated Financial Statements.                 |   |   |   |   |   |   |   |   |
|                                                                |   |   |   |   |   |   |   |   |
|                                                                |   |   |   |   |   |   |   |   |
| Union Carbide Corporation and Subsidiaries                          |
| Consolidated Statements of Comprehensive Income                     |
|                                                                |   | Three Months Ended |
|                                                                |   | March 31, |   |   | March 31, |
| In millions     (Unaudited)                |   |   | 2010 |   |   |   | 2009 |
| Net Income Attributable to Union Carbide Corporation                |   | $ | 62 |   |   | $ | 27 |   |
| Other Comprehensive Income (Loss), Net of Tax                       |   |   |   |   |   |   |   |   |
| Cumulative translation adjustment                                   |   | $ | - |   |   | $ | (5 | ) |
| Pension and other postretirement benefit plans adjustment           |   |   | 11 |   |   |   | (2 | ) |
| Net unrealized losses on investments                                |   |   | - |   |   |   | (1 | ) |
| Total other comprehensive income (loss)                             |   |   | 11 |   |   |   | (8 | ) |
| Comprehensive Income Attributable to Union Carbide Corporation      |   | $ | 73 |   |   | $ | 19 |   |
| See Notes to the Consolidated Financial Statements.                 |   |   |   |   |   |   |   |   |

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|  Union Carbide Corporation and Subsidiaries     |
|------------------------------------------------------|
|  Notes to the Consolidated Financial Statements |
|  (Unaudited)                                    |

| Note   |   | Page                                      |
|--------|--------|-------------------------------------------|
|   | A      | Consolidated Financial Statements         | 7 |
|   | B      | Recent Accounting Guidance                | 7 |
|   | C      | Restructuring                             | 8 |
|   | D      | Divestiture                               | 9 |
|   | E      | Inventories                               | 9 |
|   | F      | Other Intangible Assets                   | 10 |
|   | G      | Financial Instruments                     | 10 |
|   | H      | Fair Value Measurements                   | 11 |
|   | I      | Commitments and Contingent Liabilities    | 12 |
|   | J      | Pension and Other Postretirement Benefits | 15 |
|   | K      | Related Party Transactions                | 16 |

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Table of Contents

| 2010 Activities related to 2009RestructuringIn millions |   | Impairment of Long-lived Assets |   | SeveranceCosts |   |  Total |
|---------------------------------------------------------|--------|--------------------------------------|--------|----------------|--------|-------------|
| Reserve balance at December 31, 2009                    |   |                                 | -      |           |   | $           | 1 |   |   | $ | 1 |   |
| Adjustment to reserve                                   |   | $                                    | 5      |           |   |        | - |   |   |   | 5 |   |
| Charges against the reserve                             |   |                                 | (5     | )              |   |        | - |   |   |   | (5 | ) |
| Cash payments                                           |   |                                 | -      |           |   |        | (1 | ) |   |   | (1 | ) |
| Reserve balance at March 31, 2010                       |   |                                 | -      |           |   |        | - |   |   |   | - |   |

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| 2010 Activities related to 2008RestructuringIn millions |   | Costs associated with Exit or Disposal Activities |   |   | SeveranceCosts |   | Total |
|---------------------------------------------------------|--------|---------------------------------------------------|--------|--------|----------------|--------|-------|
| Reserve balance at December 31, 2009                    |   | $                                                 | 24     |   |           | $      | 5     |   |   | $ | 29 |   |
| Cash payments                                           |   |                                              | -      |   |           |   | (2    | ) |   |   | (2 | ) |
| Reserve balance at March 31, 2010                       |   | $                                                 | 24     |   |           | $      | 3     |   |   | $ | 27 |   |

| InventoriesIn millions |   | March 31,2010 |   |   | Dec. 31,2009 |   |
|------------------------|--------|---------------|--------|--------|--------------|--------|
| Finished goods         |   | $             | 66     |   |         | $      | 70 |   |
| Work in process        |   |          | 8      |   |         |   | 10 |   |
| Raw materials          |   |          | 46     |   |         |   | 49 |   |
| Supplies               |   |          | 75     |   |         |   | 78 |   |
| Total inventories      |   | $             | 195    |   |         | $      | 207 |   |

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| Other Intangible Assets              |   | March 31, 2010       |   |   | December 31, 2009        |   |
|--------------------------------------|--------|----------------------|--------|--------|--------------------------|--------|
| In millions                          |   | GrossCarrying Amount |   |   | Accumulated Amortization |   | Net |   |   | GrossCarrying Amount |   |   | Accumulated Amortization |   | Net |   |
| Intangible assets with finite lives: |   |                 |   |   |                     |   |   |   |   |   |   |   |   |   |   |   |   |   |
| Licenses and intellectual property   |   | $                    | 33     |   |                     | $      | (33 | ) |   |   | - |   |   | $ | 33 |   |   | $ | (33 | ) |   |   | - |   |
| Patents                              |   |                 | 2      |   |                     |   | (1 | ) |   | $ | 1 |   |   |   | 2 |   |   |   | (1 | ) |   | $ | 1 |   |
| Software                             |   |                 | 111    |   |                     |   | (103 | ) |   |   | 8 |   |   |   | 115 |   |   |   | (106 | ) |   |   | 9 |   |
| Total other intangible assets        |   | $                    | 146    |   |                     | $      | (137 | ) |   | $ | 9 |   |   | $ | 150 |   |   | $ | (140 | ) |   | $ | 10 |   |

| Estimated Amortization Expensefor Next Five YearsIn millions |   |
|--------------------------------------------------------------|--------|
| 2010                                                         |   | $ | 4 |   |
| 2011                                                         |   | $ | 3 |   |
| 2012                                                         |   | $ | 2 |   |
| 2013                                                         |   |   | - |   |
| 2014                                                         |   |   | - |   |
| 2015                                                         |   |   | - |   |

| Investing ResultsIn millions                         | Three months endedMarch 31, 2010 |
|------------------------------------------------------|----------------------------------|
| Proceeds from sales of available-for-sale securities | $2                               |

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| Fair Value of Financial Instruments:              |   |
|---------------------------------------------------|--------|
|                                              |   | March 31, 2010 |   | December 31, 2009 |
| In millions                                       |   | Cost |   | Gain |   |   | Loss |   |   | Fair Value |   | Cost |   | Gain |   |   | Loss |   |   | Fair Value |
| Marketable securities (1):                        |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |   |
| Debt securities                                   |   | $ | 20 |   |   | $ | 1 |   |   |   | - |   |   | $ | 21 |   |   | $ | 16 |   |   | $ | 1 |   |   |   | - |   |   | $ | 17 |   |
| Equity securities                                 |   |   | 1 |   |   |   | - |   |   |   | - |   |   |   | 1 |   |   |   | 1 |   |   |   | - |   |   |   | - |   |   |   | 1 |   |
| Total marketable securities                       |   | $ | 21 |   |   | $ | 1 |   |   |   | - |   |   | $ | 22 |   |   | $ | 17 |   |   | $ | 1 |   |   |   | - |   |   | $ | 18 |   |
| Long-term debt including debt due within one year |   | $ | (571 | ) |   | $ | 51 |   |   |   | - |   |   | $ | (520 | ) |   | $ | (571 | ) |   | $ | 73 |   |   |   | - |   |   | $ | (498 | ) |

| (1) | Included in “Other investments” in the consolidated balance sheets. |
|-----|---------------------------------------------------------------------------------|

| Basis of Fair Value Measurementson a Recurring Basis  |   | Significant Other Observable Inputs (Level 2) |   |   | Significant Other Observable Inputs (Level 2) |   |
|------------------------------------------------------------|--------|----------------------------------------------------|--------|--------|----------------------------------------------------|--------|
|  In millions                                          |   | March 31, 2010                                |   |   | Dec. 31, 2009                                 |   |
| Assets at fair value:                                      |   |                                               |   |   |                                               |   |
|     Debt securities (1)                |   | $                                                  | 21     |   |                                               | $      | 17 |   |

| (1) | Included in “Other investments” in the consolidated balance sheets. |
|-----|---------------------------------------------------------------------------------|

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| Receivables for Asbestos-Related CostsIn millions                             |   | March 31, 2010 |   |   | Dec. 31, 2009 |   |
|-------------------------------------------------------------------------------|--------|---------------------|--------|--------|--------------------|--------|
| Receivables for defense costs - carriers with settlement agreements           |   | $                   | 69     |   |               | $      | 91 |   |
| Receivables for resolution costs - carriers with settlement agreements        |   |                | 322    |   |               |   | 357 |   |
| Receivables for insurance recoveries - carriers without settlement agreements |   |                | 84     |   |               |   | 84 |   |
| Total                                                                         |   | $                   | 475    |   |               | $      | 532 |   |

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| Fixed and Determinable Portion of Take-or-Pay Obligationsat December 31, 2009In millions |   |
|-----------------------------------------------------------------------------------------------|--------|
| 2010                                                                                          |   | $ | 14 |   |
| 2011                                                                                          |   |   | 6 |   |
| 2012                                                                                          |   |   | 4 |   |
| 2013                                                                                          |   |   | 4 |   |
| 2014                                                                                          |   |   | 4 |   |
| 2015 and beyond                                                                               |   |   | 10 |   |
| Total                                                                                         |   | $ | 42 |   |

| Net Periodic Benefit Cost (Credit) for All Significant Plans |   | Three Months Ended |
|--------------------------------------------------------------|--------|--------------------|
| In millions                                                  |   | March 31,2010      |   | March 31,2009 |
| Defined Benefit Pension Plans:                               |   |               |   |   |   |   |
| Service cost                                                 |   | $                  | 4 |   |   | $ | 4 |   |
| Interest cost                                                |   |               | 52 |   |   |   | 56 |   |
| Expected return on plan assets                               |   |               | (66 | ) |   |   | (75 | ) |
| Amortization of prior service cost                           |   |               | 2 |   |   |   | 1 |   |
| Amortization of net loss                                     |   |               | 15 |   |   |   | 1 |   |
| Net periodic benefit cost (credit)                           |   | $                  | 7 |   |   | $ | (13 | ) |
|  Other Postretirement Benefits:                         |   |               |   |   |   |   |   |   |
| Interest cost                                                |   | $                  | 6 |   |   | $ | 8 |   |
| Net periodic benefit cost                                    |   | $                  | 6 |   |   | $ | 8 |   |

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ITEM 2. MANAGEMENT’S DISCUSSION AND ANALYSIS OF FINANCIAL CONDITION AND RESULTS OF OPERATIONS.

DISCLOSURE REGARDING FORWARD-LOOKING INFORMATION

RESULTS OF OPERATIONS

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OTHER MATTERS

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|                                              |   | 2010   |   | 2009   |
|---------------------------------------------------|--------|--------|--------|--------|
| Claims unresolved at January 1                    |   |   | 75,030 |   |   |   | 75,706 |   |
| Claims filed                                      |   |   | 2,029  |   |   |   | 2,295 |   |
| Claims settled, dismissed or otherwise resolved   |   |   | (2,220 | )      |   |   | (3,199 | ) |
| Claims unresolved at March 31                     |   |   | 74,839 |   |   |   | 74,802 |   |
| Claimants with claims against both UCC and Amchem |   |   | 23,877 |   |   |   | 24,126 |   |
| Individual claimants at March 31                  |   |   | 50,962 |   |   |   | 50,676 |   |

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| Defense and Resolution Costs |   | Three Months Ended |   |   | Aggregate costs to |   |
|------------------------------|--------|--------------------|--------|--------|--------------------|--------|
| In millions                  |   | March 31,2010      |   |   | March 31,2009      |   |   | Date as of March 31,2010 |   |
| Defense costs                |   | $                  | 14     |   |               | $      | 11 |   |   | $ | 701 |   |
| Resolution costs             |   | $                  | 12     |   |               | $      | 24 |   |   | $ | 1,492 |   |

| Receivables for Asbestos-Related CostsIn millions                            |   | March 31, 2010 |   |   | Dec. 31, 2009 |   |
|------------------------------------------------------------------------------|--------|---------------------|--------|--------|--------------------|--------|
| Receivables for defense costs - carriers with settlement agreements          |   | $                   | 69     |   |               | $      | 91 |   |
| Receivables for resolution costs - carriers with settlement agreements       |   |                | 322    |   |               |   | 357 |   |
| Receivable for insurance recoveries - carriers without settlement agreements |   |                | 84     |   |               |   | 84 |   |
| Total                                                                        |   | $                   | 475    |   |               | $      | 532 |   |

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ITEM 3.  QUANTITATIVE AND QUALITATIVE DISCLOSURES ABOUT MARKET RISK.

ITEM 4.  CONTROLS AND PROCEDURES.

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PART II – OTHER INFORMATION

ITEM 1.  LEGAL PROCEEDINGS.

ITEM 1A.  RISK FACTORS.

ITEM 6.  EXHIBITS.

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|  Union Carbide Corporation and Subsidiaries |
|--------------------------------------------------|
|  Signatures                                 |
|                                             |

|                         |   | UNION CARBIDE CORPORATION     |
|------------------------------|--------|-------------------------------|
|                         |   | Registrant                    |
|                         |   |                          |
|                         |   |                          |
| Date:  May 4, 2010 |   |                          |
|                         | By:    | /s/ RONALD C. EDMONDS         |
|                         |   | Ronald C. Edmonds             |
|                         |   | Vice President and Controller |
|                         |   | The Dow Chemical Company      |
|                         |   | Authorized Representative of  |
|                         |   | Union Carbide Corporation     |
|                         |   |                          |
|                         |   |                          |
|                         |   |                          |
|                         |   |                          |
|                         | By:    | /s/ EUDIO GIL                 |
|                         |   | Eudio Gil                     |
|                         |   | Vice President, Treasurer and |
|                         |   | Chief Financial Officer       |

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|  Union Carbide Corporation and Subsidiaries |
|--------------------------------------------------|
| Exhibit Index                                    |
|                                             |

|   |   |
|--------|--------|

| EXHIBIT NO. |                                                       DESCRIPTION  |
|-------------|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| 23          | Analysis, Research & Planning Corporation’s Consent.                                                                                                                                                                                                                                                                                   |
| 31.1        | Certification Pursuant to Section 302 of the Sarbanes-Oxley Act of 2002.                                                                                                                                                                                                                                                                         |
| 31.2        | Certification Pursuant to Section 302 of the Sarbanes-Oxley Act of 2002.                                                                                                                                                                                                                                                                         |
| 32.1        | Certification Pursuant to Section 906 of the Sarbanes-Oxley Act of 2002.                                                                                                                                                                                                                                                                         |
| 32.2        | Certification Pursuant to Section 906 of the Sarbanes-Oxley Act of 2002.                                                                                                                                                                                                                                                                              |

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