Question

3.65 grams of HCl is dissolved in 16.2 grams of water. The mole fraction of HCl in the resulting solution is:

• A. $0.4$
• B. $0.3$
• C. $0.2$
• D. $0.1$

Answer 1

The correct option is D $0.1$

$Moles=\frac{weight}{molecularweight}$

Moles of HCl $=\frac{3\cdot 65}{36\cdot 5}$$=0\cdot 1$

Moles of water $=\frac{16\cdot 2}{18}=0\cdot 9$

$\text{Mole fraction of HCl}=\frac{\text{Moles of HCl}}{\text{Total moles present in solution}}$

$=\frac{0\cdot 1}{0\cdot 1+0\cdot 9}$

$=0\cdot 1$

So, the correct option is $D$.