Use the References 1. How many ATOMS of phosphorus are present in 4.40 grams of tetraphosphorus decaoxide ?
atoms of phosphorus
2. How many GRAMS of oxygen are present in 1.01x1022 molecules of tetraphosphorus decaoxide ?
grams of oxygen

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

a chemical change results in a new substance being formed; whereas a physical change will result in a different state of matter

explanation: