What mass of Pbl2 would be produced by the reaction of 10.5G of KI?

Answer 1

molar mass KI = 166 g/mole

moles KI in 10.5 g = 10.5 g x 1 mol / 166 g = 0.0633 mols KI

Each mole of PbI₂ contains 2 moles of I, so...

0.0633 mols KI x 1 mol PbI₂ / 2 mols I = 0.0316 mols PbI₂

molar mass PbI₂ = 461 g/mol

mass of PbI₂ formed = 0.0316 mols PbI₂ x 461 g / mol = 14.6 g PbI₂ (3 sig. figs.)