Question

Find the number of moles of $CuS{O}_4.5H_{2}O$ in a pure sample that contains 0.045 moles of O-atoms.

• A. 0.5 moles
• B. 0.005 moles
• C. 50 moles
• D. 5 moles

Answer 1

The correct option is B 0.005 moles

9 moles of O-atoms are present in 1 mole of $CuS{O}_4.5H_{2}O$.
So, 0.045 moles of O-atoms will be present in
$=\frac{1}{9}\times 0.045$ moles = 0.005 moles of $CuS{O}_4.5H_{2}O$