What this calculator does
Molality of a solution works out moles of solute per kilogram of solvent, a concentration measure independent of temperature. Enter your own figures above and the answer updates as you type: nothing is fixed in the code, so the result reflects exactly the numbers you supply.
The formula this calculator evaluates is printed under the tool and explained below, so you can check the working by hand or reuse it in a spreadsheet.
The formula
Formulab = n(solute) / m(solvent), n(solute) = mass(solute) / molar mass(solute)
The inputs explained
| Field | What to enter |
|---|---|
| Mass of solute (g) | A number, measured in g. Starts at 10. |
| Molar mass of solute (g/mol) | A number, measured in g/mol. Starts at 58.44. |
| Mass of solvent (kg) | A number, measured in kg. Starts at 0.5. |
Worked examples
Every figure in the tables below is produced by this page’s own calculator at build time, so the numbers and the tool always agree. Select any row to load that scenario.
How the answer changes with mass of solute
Every other input is held at the calculator’s starting values while mass of solute varies. Select any row to load that scenario into the calculator.
How the answer changes with mass of solute