# بورون

Boron,  5B| boron (β-rhombohedral) |
| عمومي خواص |
| Pronunciation |  /ˈbɔərɒn/ |
| Allotropes | α-, β-rhombohedral, β-tetragonal (and more) |
| Appearance | black-brown |
|  |
| Boron په دوراني جدول کې |
|

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

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

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

 | – ↑ B ↓ Al
 |
| beryllium ← boron → carbon
 | ‍
 |

 |

 |
| اټومي شمیره (*Z*) | 5 |
| گروپ, پیریود | group 13 (boron group), period 2  |
| بلاک | p-block  |
| Element category |   metalloid |
| معياري اټومي وزن (*A*r) | * [10.806, 10.821]
* conventional: 10.81
 |
| Electron configuration | [He] 2s2 2p1 |
| Electrons per shell | 2, 3 |
| فزیکي خواص |
| حالت (at STP) | جامد |
| دويلې کيدو ټکى | 2349 K ​(2076 °C, ​3769 °F)  |
| يشنا ټکی | 4200 K ​(3927 °C, ​7101 °F)  |
| Density when liquid, at m.p. | 2.08 g/cm3 |
| Heat of fusion | 50.2 kJ/mol  |
| Heat of vaporization | 508 kJ/mol  |
| Molar heat capacity | 11.087 J/(mol·K)  |
| **Vapor pressure**

| *P* (Pa) | 1
 | 10
 | 100
 | 1 k
 | 10 k
 | 100 k
 |
| --- | --- | --- | --- | --- | --- | --- |
| at *T* (K) | 2348
 | 2562
 | 2822
 | 3141
 | 3545
 | 4072
 |

 |
| اټومي خواص |
| Oxidation states | **3**, 2, 1, −1, −5 ​(a mildly acidic oxide) |
| Electronegativity | Pauling scale: 2.04  |
| Ionization energies | * 1st: 800.6 kJ/mol
* 2nd: 2427.1 kJ/mol
* 3rd: 3659.7 kJ/mol
* (more)
 |
| Atomic radius | empirical: 90 pm  |
| Covalent radius | 84±3 pm  |
| Van der Waals radius | 192 pm  |
| Miscellanea |
| Crystal structure |  ​rhombohedralRhombohedral crystal structure for boron |
| Speed of sound thin rod | 16,200 m/s (at 20 °C)  |
| Thermal expansion | β form: 5–7 µm/(m·K) (at 25 °C)  |
| د تودوخې تېرېدنه | 27.4 W/(m·K)  |
| Electrical resistivity | ~106 Ω·m (at 20 °C)  |
| Magnetic ordering | diamagnetic  |
| Magnetic susceptibility (*χ*mol) | −6.7·10−6 cm3/mol |
| Mohs hardness | ~9.5  |
| CAS Number | 7440-42-8  |
| History |
| Discovery | Joseph Louis Gay-Lussac and Louis Jacques Thénard (30 June 1808) |
| First isolation | Humphry Davy (9 July 1808) |
| Main isotopes of boron |
|

| آيسو­ټوپ
 | Abun­dance
 | نیم ژوند (*t*1/2) | Decay mode
 | Pro­duct
 |
| --- | --- | --- | --- | --- |
| 10B
 | 20%
 | stable
 |
| 11B
 | 80%
 | stable
 |

 |
| 10B content may be as low as 19.1% and as high as 20.3% in natural samples. 11B is the remainder in such cases. |
|

**بورون** (په انگرېزي: *Boron*) له کیمیاوي عناصرو څخه یو دی چې په تناوبي جدول کې د **B** سمبول او ۵ اتمي شمېرې په وسیله ښودل شوی دی.

## مشخصات

## تاریخچه

## مرکبات

## د استعمال ځایونه

## سرچينې

|  |
| --- |
|

 دا ليکنه نابشپړه ده، تاسې ددې ليکنې په بشپړولو کې د ويکيپېډيا سره مرسته کولای شئ.

 |