Three nails have a mass of 3.05 g. How many moles of iron do they contain?
3.05gFe x 1 mole/55.85gFe = 0.0546moleFe
A student needs to use 0.575 moles of sodium chloride (NaCl) in an experiment. How many grams should they obtain?
0.575 moleNaCl x 58.44gNa Cl / 1 mole Na Cl = 33.6gNa Cl
Suppose that you obtained 3.50 g of Na2CO3, sodium carbonate. How many moles would you have?
Hint: What is the molar mass of sodium carbonate.
3.50gNa 2 CO 3 x 1moleNa 2 CO 3 / 105.99gNa 2 CO 3 = 0.0473moleNa 2 CO 3
A mole is the amount of substance in the International System of Units.