Molar MassMolar mass of dinitrogen monoxide (N2O)
The molar mass of dinitrogen monoxide, N2O, is 44.01 g/mol. One mole of it, which is 6.022 × 1023 molecules, has a mass of 44.01 grams.
44.01 g/mol
2 × 14.007 + 15.999 = 44.013 · 3 atoms in the formula · also called nitrous oxide, laughing gas
About dinitrogen monoxide
Dinitrogen monoxide is laughing gas, used as a mild anaesthetic. It has the same molar mass, to two figures, as carbon dioxide.
Other names: nitrous oxide, laughing gas.
The working
The formula N2O has 2 nitrogen atoms and 1 oxygen atom, 3 atoms in all. Multiply each count by the atomic weight of the element and add:
| Element | Atoms | Atomic weight | Total | Share by mass |
|---|---|---|---|---|
| Nitrogen (N) | 2 | 14.007 | 28.014 | 63.65% |
| Oxygen (O) | 1 | 15.999 | 15.999 | 36.35% |
2 × 14.007 + 15.999 = 44.013 g/mol
With the rounded atomic masses used in many school books (N = 14, O = 16) the answer is 44 g/mol. The difference from 44.01 is too small to matter in most school sums.
Percentage composition
By mass, N2O is 63.65% nitrogen and 36.35% oxygen. The largest share comes from nitrogen. In a 100 g sample there are 63.6 g of nitrogen and 36.4 g of oxygen.
Worked examples
Grams to moles. How many moles are in 10 g of N2O? Divide the mass by the molar mass: 10 ÷ 44.01 = 0.2272 mol.
Moles to grams. What is the mass of 1.5 mol of N2O? Multiply: 1.5 × 44.01 = 66.02 g.
Counting particles. 10 g contains 0.2272 mol × 6.022 × 1023 = 1.368 × 1023 molecules, and 4.105 × 1023 atoms in all.
As a gas. At 0 °C and 1 atmosphere one mole of an ideal gas occupies 22.4 litres, so the density of N2O is about 44.01 ÷ 22.4 = 1.96 g per litre. Air averages about 29 g/mol, so this gas is heavier than air.
Quick conversion tables
| Amount | Mass |
|---|---|
| 0.1 mol | 4.401 g |
| 0.5 mol | 22.01 g |
| 1 mol | 44.01 g |
| 2 mol | 88.03 g |
| 5 mol | 220.1 g |
| Mass | Moles |
|---|---|
| 1 g | 0.02272 mol |
| 10 g | 0.2272 mol |
| 100 g | 2.272 mol |
| 1 kg | 22.72 mol |
For other amounts use the grams and moles converter.
Questions people ask
What is the molar mass of N2O?
The molar mass of dinitrogen monoxide (N2O) is 44.01 g/mol, or 44.013 g/mol before rounding, using IUPAC abridged atomic weights.
How many moles are in 100 g of N2O?
100 ÷ 44.01 = 2.272 mol.
What is the mass of one molecule of N2O?
Divide the molar mass by the Avogadro constant: 44.01 ÷ 6.022 × 1023 = 7.309 × 10-23 g.
What is the percentage of nitrogen in N2O?
Nitrogen makes up 63.65% of the mass of N2O: 2 × 14.007 ÷ 44.013 × 100.
Which values? This site uses the abridged standard atomic weights published by IUPAC (CIAAW), read on 12 November 2026. Your textbook or question paper may round them differently, for example H = 1 and O = 16, so its answer can differ slightly. In an exam, use the values the paper gives.