stoichiometry question

Question

Determine the moles if given 36.4g of potassium.

Answer 1

When trying to convert from grams to moles, you must divide by the molar mass.

1. look up the molar mass of K on the periodic table (39.10g)
2. Divide your given: 36.4 g K / 39.10 = 0.931 mol K

Answer 2

If you look up potassium on the Periodic Table you'll see it says 39.098 which means the molar mass is 39.098 g/mol. So: