To calculate the percent composition of copper sulfate pentahydrate CuSO4 5H2O , we first need to determine the molar mass of each element in the compound and then find the percentage of each element.First, let's find the molar mass of each element in the compound:- Copper Cu : 63.55 g/mol- Sulfur S : 32.07 g/mol- Oxygen O : 16.00 g/mol- Hydrogen H : 1.01 g/molNow, let's find the molar mass of the entire compound:CuSO4 5H2O = 1 63.55 + 1 32.07 + 4 16.00 + 5 2 1.01 + 5 16.00 = 63.55 + 32.07 + 64.00 + 10.10 + 80.00= 249.72 g/molNext, we'll calculate the percent composition of each element in the compound:- Percent of Copper Cu : 63.55 g/mol 249.72 g/mol 100% = 25.45%- Percent of Sulfur S : 32.07 g/mol 249.72 g/mol 100% = 12.85%- Percent of Oxygen O : [ 4 16.00 + 5 16.00 ] g/mol 249.72 g/mol 100% = 57.56%- Percent of Hydrogen H : 10.10 g/mol 249.72 g/mol 100% = 4.04%So, the percent composition of copper sulfate pentahydrate CuSO4 5H2O is:- Copper Cu : 25.45%- Sulfur S : 12.85%- Oxygen O : 57.56%- Hydrogen H : 4.04%