If you reacted 93.7 grams of iron with excess copper sulfate solution, what mass of copper would you expect to make? You may need to balance the equation first. Fe + CuSO4 - > Cu + FeSO4 A. 89.18 grams

B. 106.25 grams

C. 1.67 grams

D. 104.5 grams

1) Chemical equation

Fe + CuSO4 - - > Cu + FeSO4

It is already balanced

2) Molar ratios

1 mol Fe : 1 mol CuSO4 : 1 mol Cu : 1 mol FeSO4

3) atomic masses of Fe and Cu

Fe: 55.8 g/mol

Cu: 63.5 g/mol

4) number of moles of Fe

number of moles = mass in grams / atomic mass = 93.7 g / 55.8 g/mol = 1.679 mol

5) number of moles of Cu:

1 mol Fe / 1 mol Cu = > 1.679 mol Fe / 1.679 mole Cu

5) mass of Cu in 1.679 moles Cu

mass = atomic mass * number of atoms = 63.5 g/mol * 1.679 moles = 106.6 g = 107 rounded to 3 significant figures.

=> Answer is the option B (although the question should have 3 significant figures).