Question

At a certain temperature, the solubility of n2 gas in water at 3.08 atm is 72.5 mg of n2 gas/100 g water . calculate the solubility of n2 gas in water, at the same temperature, if the partial pressure of n2 gas over the solution is increased from 3.08 atm to 8.00 atm . express your answer numerically to three significant figures.

Answer 1

According to Henry's law, solubility of solution is directly proportional to partial pressure thus,

$\frac{S_{1}}{P_{1}}=\frac{S_{2}}{P_{2}}$

Solubility at pressure 3.08 atm is 72.5/100, solubility at pressure 8 atm should be calculated.

Putting the values in equation:

$\frac{0.725}{3.08}=\frac{S_{2}}{8}$

On rearranging,

$S_{2}=\frac{0.725\times 8}{3.08}=1.88$

Therefore, solubility will be 1.88 mg of $N_{2}$ gas in 1 g of water or, 188 mg of tex]N_{2}[/tex] gas in 100 g of water.