Enter the total substance mass (g) and the isotopes percent mass of the total mass (%) into the Isotope Mass Calculator. The calculator will evaluate and display the Isotope Mass.

## Isotope Mass Formula

The following formula is used to calculate the Isotope Mass.

IM = TM * PM/100
• Where IM is the Isotope Mass (g)
• TM is the total substance mass (g)
• PM is the isotopes percent mass of the total mass (%)

To calculate an isotope mass, multiply the total substance mass by the isotope percentage.

## How to Calculate Isotope Mass?

The following example problems outline how to calculate Isotope Mass.

Example Problem #1:

1. First, determine the total substance mass (g).
• The total substance mass (g) is given as: 89.
2. Next, determine the isotopes percent mass of the total mass (%).
• The isotopes percent mass of the total mass (%) is provided as: 30.
3. Finally, calculate the Isotope Mass using the equation above:

IM = TM * PM/100

The values given above are inserted into the equation below and the solution is calculated:

IM = 89 * 30/100 = 26.7 (g)

Example Problem #2:

For this problem, the variables needed are provided below:

total substance mass (g) = 90

isotopes percent mass of the total mass (%) = 24

This example problem is a test of your knowledge on the subject. Use the calculator above to check your answer.

IM = TM * PM/100 = ?