Question

4) How many moles are in each elemental sample?

a. 9.01 g Be
b. 42.03 g P
c. 71.90 g CI

Answer 1

1 mole

The first step is to calculate the molar mass (gram formula weight) of MgCl2. Molar mass = (24.31 + 2 × 35.45) = 95.21 g mol–1 i.e. 95.21 g of MgCl2 is exactly 1 mole