Question

Calculate the mole fraction of h2so4 when 35.25 gm of h2so4 is dissolved in 100 gm of water​

Answer 1

$\sf\huge\bold{Answer:}$

Given :

$\sf H_{2} SO_{4} = 35.25 \: gm$

$\sf H_{2} O = 100 \: gm$

To find :

Mole fraction of $\sf H_{2} SO_{4}$

Solution :

$\fbox{Formula for number of moles :}$

$\sf\purple{:⟶no.of \: moles = \frac{given \: mass}{molar \: mass}}$

$\sf For\: H_{2} SO_{4}$

Given mass = 35.25 gm

Molar mass = 98 gm

$\sf:⟶moles \: of \: H_{2} SO_{4} = \frac{35.25gm}{98gm}$

$\sf:⟶moles \: of \: H_{2} SO_{4} =$$\displaystyle{\sf { \cancel{ \frac{35.25gm}{98gm} }}}$

$\sf:⟶moles \: of \: H_{2} SO_{4} ≈ 0.359$

$\sf For\: H_{2} O$

Given mass = 100 gm

Molar mass = 18 gm

$\sf H_{2} O =\frac{100gm}{18gm}$

${\sf H_{2} O =}$$\displaystyle{\sf { \cancel{ \frac{100gm}{18gm} }}}$

${\sf H_{2} O ≈ 5.555 }$

$\fbox{Formula for mole fraction}$

$\sf\purple{Mole \: fraction \: of \: H_{2} SO_{4} = \frac{moles \: of \:H_{2} SO_{4} }{moles \: of \: H_{2} SO_{4} + \: moles \: of \: H_{2} O }}$

$\sf{:⟶Mole \: fraction \: of \: H_{2} SO_{4} = \frac{0.359 }{0.359+ 5.555 }}$

$\sf{:⟶Mole \: fraction \: of \: H_{2} SO_{4} = \frac{0.359 }{0.359+ 5.555 }}$

$\sf{:⟶Mole \: fraction \: of \: H_{2} SO_{4} = \frac{0.359 }{5.909 }}$

$\sf{:⟶Mole \: fraction \: of \: H_{2} SO_{4} ≈ 60.75}$

$\sf\huge\purple{Mole \: fraction \: of \: H_{2} SO_{4} ≈ 60.75}$