the number grams of lead chromate formed is calculated as follows
write the reaction equation
Pb(No3)2 + K2CrO4 ----> 2KNO3 + PbCrO4
then calculate moles of each reagent
that is moles of Pb(No3)2 = 15 x0.40/1000= 6 x10^-3 moles
moles of K2CrO4 = 15 x0.15/1000= 2.25 x10^-3moles
K2CrO4 moles are the limiting reagent therefore by use of reacting ratio between K2CrO4 to PbcrO4 the moles of pbcro4 is
2.25 x10^-3 moles
mass is therefore = (2.25 x10^-3) x 323.19(molar mass of PbCrO4) = 0.727 g
