Question

$6.02\times 10^{20}$ molecules of urea are present in $100mL$ solution. The concentration of urea solution is :

• A. $0.1M$
• B. $0.01M$
• C. $0.02M$
• D. $0.001M$

Answer 1

Answer: (B)

Conc. $=\frac{n_{\text{urea }}}{V(L)}=\frac{6.02\times {\left(10\right)}^{20}}{6.02\times {\left(10\right)}^{23}}\times \frac{1}{0.1}$
$=0.01M$