Lead nitrate can be decomposed by heating. Theoretically, the chemical reaction should produce 6.7 g of PbO. What is the percent yield of the reaction if 6.43 g of PbO are produced when the lead nitrate is heated? 2Pb(NO3)2(s) -> 2PbO(s) + 4NO2(g) + O2(g)

A-44%

B-56%

C-67%

D-82%

E-96%

F-100%

a. the law of proportion states the combination of 2 atoms in a specific ratio to produce multiple compounds such as the given statement of question ‘1st compound contains 88.8 % cu ’ indicates 88.8 g of cu is present along with 11.2 g oxygen in 100 g of compound whereas the statement ‘2st compound contains 79.9 % cu ’ indicates 79.9 g of cu is present along with 20.1 g oxygen in 100 g of compound

1st compound contains 88.8 g cu

for cu

m = 63 g /mol

atomic % = 88.8 /63 = 1.42

for o

m = 16 g /mol

atomic % = 11.2 /16 = 0.7

b. the emperical formula of 1st compound is

cu1.4o0.7

cu2o