Room temperature in kelvin
Celsius and kelvin have the same step size; only the zero point moves.
K = °C + 273.15
25 + 273.15 = 298.15 K
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Chemistry unit converter
Convert between the units chemistry keeps switching between: temperature, energy, pressure, amount of substance and atomic-scale length. Exact SI constants are used, so moles to particles and electronvolts to joules come out right.
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Unit converter
The units chemistry keeps switching between — temperature, energy, pressure, amount and atomic-scale length.
Worked examples
One atmosphere in kilopascals
One standard atmosphere is defined as exactly 101 325 pascals.
1 atm = 101,325 Pa
101,325 Pa ÷ 1,000 = 101.325 kPa
Open this example in the toolHalf a mole in particles
Multiply by the Avogadro constant, which is exact by definition.
N = n × NA
0.5 mol × 6.02214076 × 10²³ mol⁻¹ = 3.0111 × 10²³
Open this example in the toolHow it works
Every value is converted to a base unit and back: kelvin for temperature, joules for energy, pascals for pressure, moles for amount and metres for length. Temperatures need an offset as well as a factor, which is why 0 °C is 273.15 K and not 0 K.
The constants are the exact SI values: the Avogadro constant is 6.02214076 × 10²³ per mole and one electronvolt is 1.602176634 × 10⁻¹⁹ J. A calorie is the thermochemical calorie, 4.184 J, and an atmosphere is 101 325 Pa.
Limits
- mmHg and torr are treated as the same unit; they differ by about one part in seven million.
- The kJ/mol option turns a molar energy into the energy of one particle, so pair it with joules or electronvolts.
- Results are rounded to eight decimal places, or shown in scientific notation when very large or very small.
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