Stoichiometry & gases · SL/HL
Moles, Mass & Particles Calculator
Choose the quantity to calculate. Molar mass is entered in g mol⁻¹ and mass in g.
Your values
Start with the example or enter your own values. Use a dot for decimals and e for scientific notation.
Calculated locally. No account or input upload.
Result & working
ExampleThe calculator is loading. The worked example is also shown below.
Step-by-step working
The formula
n = m/M
m = nM
N = nNₐ
Nₐ = 6.02214076 × 10²³ mol⁻¹
| Symbol | Meaning |
|---|---|
| n | Amount of substance in mol. |
| m | Mass in g when M is in g mol⁻¹. |
| M | Molar mass in g mol⁻¹. |
| N | Number of specified particles. |
When to use this calculator
Use stoichiometric coefficients on amounts in moles, not directly on masses. State what the “particles” are: atoms, molecules, ions or formula units.
Worked example
The page opens with these example values. The result below is pre-generated for reference.
- n = m/M = 5.85 / 58.44 = 0.1001027 mol
- Check: g ÷ (g mol⁻¹) = mol.
0.1001027 mol
Common mistakes
- Do not multiply by molar mass when you need moles; divide mass by molar mass.
- A chemical formula determines molar mass; this tool does not infer the formula from a name.