Question

Total number of atoms represented by the compound $CuS{O}_4.5H_{2}O$ is:

• A. 27
• B. 21
• C. 5
• D. 8

Answer 1

Answer: (B)

Total number of atoms in
$CuS{O}_4.5H_{2}O$ are $1+1+4+5(2+1)=6+5\times 3$
$=21$
$\therefore$ $CuS{O}_4.5H_{2}O$ has 21 atoms.