Chemistry
Molar Ratio Calculator
Convert moles of one substance into moles of another using the balanced equation coefficients.
Your inputs
Change any value to update the result instantly.
Moles of substance B
4 mol
Mole ratio used
1 : 2 (A : B)
Mass of B
72.06 g
Moles of A supplied
2 mol
Reading
More of B is formed or consumed than A
The coefficients must come from a balanced equation — balance it first with the equation balancer if you are unsure.
What this calculator does
Converts moles of one substance into moles of another using the coefficients of the balanced equation.
What your result means
The amount of the second substance produced or consumed when the stated amount of the first reacts completely.
Formula and working
n_B = n_A × (ν_B ÷ ν_A)
- 1
Collect the inputs
Moles of substance A you have = 2 mol; Coefficient of A (ν_A) = 1; Coefficient of B (ν_B) = 2; Molar mass of B (optional) = 18.015 g/mol
- 2
Apply the formula
n_B = n_A × (ν_B ÷ ν_A)
- 3
Result
Moles of substance B = 4 mol
Frequently asked questions
Symbols and assumptions
- n_A, n_B
- Moles of each substance
- nu_A, nu_B
- Balanced coefficients
- • The equation is already balanced.
- • The reaction goes to completion with no side reactions.
Sources and review
Reviewed 2026-09-22 · Next review 2027-09-22
- • Coefficients from an unbalanced equation give a wrong ratio. Limiting-reagent effects are not considered here.
Important limitation
This is an educational estimate based only on the values and formula shown. Verify current rates, rules, units, and professional standards before relying on the result. It is not personalized financial or investment advice.
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