Question

The number of molecules of water in 333 g of $A{l}_2(S{O}_4{)}_3$.18$H_{2}O$ is

• A. 18.0 x 6.02 x 10²³
• B. 9.0 x 6.02 x 10²³
• C. 18.0
• D. 36.0

Answer 1

The correct option is B

9.0 x 6.02 x 10²³

Molecular wt of$A{l}_2(S{O}_4{)}_3$.18$H_{2}O$

=2$\times$27+96$\times$3+18$\times$18

=666 has 18 moles of water

In 333 g no .of moles of $H_{2}O$=9