Question

Dawn is in a chemistry lab. She has container of a chemical. The chemical formula for the substance is on the label. Dawn measured a small portion of the mass on a balance beam. What will she need to do to find the number of moles in the substance?

Answer 1

To find the number of moles of the substance, Dawn will need to know the molar mass of the substance. The molar mass is the mass of one mole of the substance, expressed in grams per mole (g/mol).

Dawn can calculate the number of moles of the substance using the following formula:

moles = mass / molar mass

Where mass is the measured mass of the substance in grams.

To find the molar mass of the substance, Dawn will need to look up the atomic masses of the elements in the chemical formula of the substance, and multiply them by the number of atoms of each element in the formula. Then, she can add up the results to get the molar mass of the substance in g/mol.

Once Dawn has calculated the molar mass of the substance and measured its mass, she can use the formula above to calculate the number of moles of the substance.

Hope this helps!