Final answer:
To find the percent composition of ZnSO4 x H2O, divide the mass of ZnSO4 by the total mass of the sample and multiply by 100. The percent composition is 55.66%.
Step-by-step explanation:
In this question, we are given that a 12.0g sample of ZnSO4 · H2O is dehydrated to produce 6.74g of ZnSO4. To find the percent composition of the compound, we need to calculate the amount of ZnSO4 in the original sample and divide it by the total mass of the sample, then multiply by 100.
The molar mass of ZnSO4 is 161.46 g/mol. So, the amount of ZnSO4 in the 6.74g of ZnSO4 produced is:
6.74g ÷ 161.46 g/mol = 0.0417 mol
Now, we can calculate the percent composition:
(0.0417 mol ZnSO4 · 161.46 g/mol) ÷ 12.0 g = 55.66%