Question

6.02 × 1020 molecules of urea are present in 100 ml of its solution. The concentration of urea solution is :

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

Answer 1

Answer: (B)

0.01 M

Answer 2

Moles of urea = $\frac { 6.02 \times 10 ^ { 20 } } { 6.02 \times 10 ^ { 23 } } = 10 ^ { - 3 }$moles

Concentration (molarity) of solution =× 1000 = 0.01 M.