Question

$3.01\times {10}^{23}$ NaCl ion pairs are dissolved in water and diluted to a volume of 10 litres. The molar concentration of the solution is:

• A. $0.5M$
• B. $0.25M$
• C. $1M$
• D. $0.05M$

Answer 1

The correct option is D $0.05M$

$Molarity=\frac{No.ofmoles}{Volume\left(L\right)}$

$Numberofmoles=\frac{3.01\times {10}^{23}}{6.02\times {10}^{23}}=\frac{1}{2}$

$\therefore Molarity=\frac{1}{2\times 10}$

$=0.05M$

Option D is correct.