# Appendix C: Units and Conversion Factors

## Units of Length, Mass, Energy & Pressure

Table C.1: Units of Length
Unit Equivalent Units
meter (m) = 39.37 inches (in.)

= 1.094 yards (yd)
centimeter (cm) = 0.01 m (exact, definition)
millimeter (mm) = 0.001 m (exact, definition)
kilometer (km) = 1000 m (exact, definition)
angstrom (Å) = 10–8 cm (exact, definition)

= 10–10 m (exact, definition)
yard (yd) = 0.9144 m
inch (in.) = 2.54 cm (exact, definition)
mile (US) = 1.60934 km
Table C.2: Units of Volume
Unit Equivalent Units
liter (L) = 0.001 m3 (exact, definition)

= 1000 cm3 (exact, definition)

= 1.057 (US) quarts
milliliter (mL) = 0.001 L (exact, definition)

= 1 cm3 (exact, definition)
microliter (μL)(μL) = 10–6 L (exact, definition)

= 10–3 cm3 (exact, definition)
liquid quart (US) = 32 (US) liquid ounces (exact, definition)

= 0.25 (US) gallon (exact, definition)

= 0.9463 L
dry quart = 1.1012 L
cubic foot (US) = 28.316 L

Table C.3: Units of Mass
Unit Equivalent Units
gram (g) = 0.001 kg (exact, definition)
milligram (mg) = 0.001 g (exact, definition)
kilogram (kg) = 1000 g (exact, definition)

= 2.205 lb
ton (metric) =1000 kg (exact, definition)

= 2204.62 lb
ounce (oz) (avoirdupois) = 28.35 g
pound (lb) (avoirdupois) = 0.4535924 kg
ton (short) =2000 lb (exact, definition)

= 907.185 kg
ton (long) = 2240 lb (exact, definition)

= 1.016 metric ton
Table C.4: Units of Energy
Unit Equivalent Units
4.184 joule (J) = 1 thermochemical calorie (cal)
1 thermochemical calorie (cal) = 4.184 × 107  erg
erg = 10–7 J (exact, definition)
electron-volt (eV) = 1.60218 × 10−19 J = 23.061 kcal mol−1
liter∙atmosphere = 24.217 cal = 101.325 J (exact, definition)
nutritional calorie (Cal) = 1000 cal (exact, definition) = 4184 J
British thermal unit (BTU) = 1054.804 J[1]

Table C.5: Units of Pressure
Unit Equivalent Units
torr = 1 mm Hg (exact, definition)
pascal (Pa) = N m–2 (exact, definition)

= kg m–1 s–2 (exact, definition)
atmosphere (atm) = 760 mm Hg (exact, definition)

= 760 torr (exact, definition)

= 101,325 N m–2 (exact, definition)

= 101,325 Pa (exact, definition)
bar = 105 Pa (exact, definition)

= 105 kg m–1 s–2 (exact, definition)