Calculation history
Formula used
M is the compound molar mass. Each n value counts one element. Each A value is its atomic mass.
Mass equals moles multiplied by molar mass. Moles equal mass divided by molar mass. Particle count uses Avogadro’s constant.
How to use
- Select the required calculation mode.
- Enter potassium or a potassium-containing chemical formula.
- Choose natural, isotopic, or custom potassium mass.
- Enter relevant mass, moles, atoms, or formula units.
- Set purity, output units, and rounding preferences.
- Press Calculate and review every displayed step.
Potassium compound examples
| Formula | Compound | Approximate molar mass | Potassium atoms |
|---|---|---|---|
| K | Potassium | 39.0983 g/mol | 1 |
| KCl | Potassium chloride | 74.5483 g/mol | 1 |
| KOH | Potassium hydroxide | 56.1053 g/mol | 1 |
| KNO₃ | Potassium nitrate | 101.1023 g/mol | 1 |
| K₂SO₄ | Potassium sulfate | 174.2526 g/mol | 2 |
| KMnO₄ | Potassium permanganate | 158.0323 g/mol | 1 |
Frequently asked questions
What is potassium’s molar mass?
Natural potassium has an average molar mass of 39.0983 g/mol.
Why does potassium use an average atomic mass?
Natural samples contain isotopes in characteristic abundance proportions.
Can this calculator use potassium isotopes?
Yes. Select potassium-39, potassium-40, potassium-41, or custom mass.
Does it support hydrates?
Yes. Enter hydrate separators using a period or middle dot.
Can it parse nested brackets?
Yes. Parentheses, square brackets, and braces are supported.
How is potassium mass percentage calculated?
Divide potassium’s contribution by total compound molar mass.
How does purity affect required mass?
Lower purity requires more sample to supply equal pure material.
What are formula units?
Formula units count ionic compound particles represented by one formula.
Are displayed values suitable for laboratory work?
Confirm atomic weights, purity certificates, and measurement uncertainty first.
Important note
Atomic weights can vary slightly by reference standard. Isotopic calculations require suitable mass data. Use verified laboratory data before making critical chemical decisions.