# General Chemistry/Units
## SI Fundamental Units

These are the seven basic SI units from which all other units are constructed.
| Quantity | Symbol | Unit | Unit Symbol |
| Length | l | metre/meter | m |
| Time | t | second | s |
| Mass | m | kilogram | kg |
| Thermodynamic temperature | T | kelvin | K |
| Amount of substance | n | mole | mol |
| Electrical current | I | ampere | A |
| Luminous intensity | I$_V$ | candela | cd |

## SI Derived Units

All other units are derived units. They are built from fundamental units. This is a small selection of units that may be found in General Chemistry.
| Quantity | Symbol | Unit | Unit Symbol | Derived From |
| Force | F | newton | N | kg·m·s$^{-2}$ |
| Energy | U | joule | J | kg·m$^2$·s$^{-2}$ |
| Pressure | P | pascal | Pa | kg·m$^{-1}$·s$^{-2}$ |
| Power | | watt | W | kg·m$^2$·s$^{-3}$ |
| Electrical charge | Q | coulomb | C | A·s |
| Electrical potential | V | volt | V | J·C$^{-1}$ |

## SI Prefixes

A prefix appears before a unit's symbol when expressing very large or very small quantities. For example: 0.001 kg = 1 g = 1000 mg.
| 1000$^n$ | 10$^n$ | Prefix | Symbol | Decimal |
| 1000$^8$ | 10$^{24}$ | yotta | Y | 1 000 000 000 000 000 000 000 000 |
| 1000$^7$ | 10$^{21}$ | zetta | Z | 1 000 000 000 000 000 000 000 |
| 1000$^6$ | 10$^{18}$ | exa | E | 1 000 000 000 000 000 000 |
| 1000$^5$ | 10$^{15}$ | peta | P | 1 000 000 000 000 000 |
| 1000$^4$ | 10$^{12}$ | tera | T | 1 000 000 000 000 |
| 1000$^3$ | 10$^9$ | giga | G | 1 000 000 000 |
| 1000$^2$ | 10$^6$ | mega | M | 1 000 000 |
| 1000$^1$ | 10$^3$ | kilo | k | 1 000 |
| | 10$^2$ | hecto | h | 100 |
| | 10$^1$ | deca | da | 10 |
| 1000$^0$ | 10$^0$ | (none) | (none) | 1 |
| | 10$^{−1}$ | deci | d | 0.1 |
| | 10$^{−2}$ | centi | c | 0.01 |
| 1000$^{−1}$ | 10$^{−3}$ | milli | m | 0.001 |
| 1000$^{−2}$ | 10$^{−6}$ | micro | µ | 0.000 001 |
| 1000$^{−3}$ | 10$^{−9}$ | nano | n | 0.000 000 001 |
| 1000$^{−4}$ | 10$^{−12}$ | pico | p | 0.000 000 000 001 |
| 1000$^{−5}$ | 10$^{−15}$ | femto | f | 0.000 000 000 000 001 |
| 1000$^{−6}$ | 10$^{−18}$ | atto | a | 0.000 000 000 000 000 001 |
| 1000$^{−7}$ | 10$^{−21}$ | zepto | z | 0.000 000 000 000 000 000 001 |
| 1000$^{−8}$ | 10$^{−24}$ | yocto | y | 0.000 000 000 000 000 000 000 001 |

## Solution Concentration Units

| Quantity | Symbol | Units | Description |
| Molarity | M | mol/L | moles of solute per liter of solution |
| Molality | m | mol/kg | moles of solute per kilogram of solvent |
| Mole Fraction | χ | (none) | moles of solute per moles of solution |
| Parts per million | ppm | (none) | milligrams of solute per kilogram of solution |
| Parts per billion | ppb | (none) | micrograms of solute per kilogram of solution |

## Other Useful Units
### Volume

| Volume Unit | Conversion | Mass of Water (4 °C) |
| 1 L | = 1000 cm$^3$ | 1 kg |
| 1 cm$^3$ | = 1 mL | 1 g |
| 1 m$^3$ | = 1000 L | 1000 kg |

### Pressure

| Name | Symbol | Conversion | Conversion |
| Atmosphere | atm | = 760 torr | = 101.325 kPa |
| Pascal | Pa | ≈ 7.5 x 10$^{-3}$ torr | |
| Torr (mm Hg) | torr | ≈ 133.3 Pa | |
| Pound-per-square inch | psi | ≈ 51.7 torr | ≈ 6.894 kPa |

### Temperature

One degree Celsius is equal to one Kelvin (in magnitude).
| Name | Symbol | Abs. Zero | M.P. of Water | B.P. of Water |
| Fahrenheit | °F | -456.67 °F | 32 °F | 212 °F |
| Celsius | °C | -273.15 °C | 0 °C | 100 °C |
| Kelvin | K | 0 K | 273.15 K | 373.15 K |
* Notice it is not "degrees Kelvin".