The formula mass of Fe(NO₃)₂ is ____?

180 amu

160 amu

170 amu

None of these

Fe = 56, N = 14 × 2 = 28, O = 16 × 6 = 96 → Total = 56 + 28 + 96 = 180 amu

This is the correct formula mass for Iron (II) Nitrate, Fe(NO₃)₂.