# Grams to Moles Calculator

Enter the total number of grams of a substance, and the moles per gram of that substance to calculate the total number of moles

## Grams to moles formula

The following formula is used to convert the total number of grams of a substance to the total number of moles.

m = M * mpg

• Where m is the total number of moles
• M is the total mass in grams
• mpg is the moles per gram of the substance

For this formula the mass and moles per unit pass could be switched to any unit you have. For example, if you have a mass of 2 lbs, you must calculated or determine the number of moles per pound, and then the total number of moles can be calculated.

## How to convert grams to moles

The following is a step by step guide on how one might convert the total amount of grams of a substance to the total number of moles. For this example we will assume we have a solution with two different substances, at 65% and 35% concentration by weight.

1. The first step is to calculate the total number of grams for the substance we want to convert to moles. It’s assumed that the total weight is 100 grams and we are trying to find the weight of the 65% concentration by weight substance. Therefore, we must multiply 100*65% = grams.
2. Next, the total number of moles per gram of the substance must be either calculated or measured. This is solely determined by the elements in the substance. The learn more about how this is calculated, visit this blog post. For this example we are going to assume that we know this to be 1000 moles per gram. Note that this number is very very low, and only used to make this simpler.
3. The final step is the plug the information we gathered above into the formula, or calculator if you’re feeling lazy. We find m = 65 * 1000 = 65,000 moles.
4. Analyze the results to see if the answer makes logical since. if this was a real problem, in this step you would find that the answer does not make logical since because the total moles in a gram of substance should be orders of magnitude greater than what it was in this problem.

More Science and Engineering Calculators