Question

Henry's constant (in $kbar$) for four gases $\alpha ,\beta ,\gamma$ and $\delta$ in water at $298K$ is given below :

(density of water $=10^{3}kg{m}^{-3}$ at $298K$ )
This table implies that :

• A. $\alpha$ has the highest solubility in water at a given pressure
• B. solubility of $\gamma$ at $308K$ is lower than at $298K$
• C. The pressure of a $55.5$ molal solution of $\gamma$ is $1bar$
• D. The pressure of a $55.5$ molal solution of $\delta$ is $250$ bar

Answer 1

Answer: (D)

(a) From Henry's law $p=K_H(x)$
Higher the value of $K_H$ smaller will be the solubility of the gas, so $\gamma$ is more soluble.
(b) Though solubility of gases will decrease with increase in temperature but this conclusion can not be drawn from the given table.
(c) For $\gamma$
$(p{)}_{\gamma }={\left(K_H\right)}_{\gamma }\cdot (x{)}_{\gamma }=2\times 10^{-5}\left[\frac{55.5}{55.5+\frac{1000}{18}}\right]$
$=10^{-5}k\text{ bar }=10^{-2}bar$
(d) For $\delta \Rightarrow$
$p_{\delta }={\left(K_H\right)}_{\delta }\cdot (x{)}_{\delta }=0.5\left[\frac{55.5}{55.5+\frac{1000}{18}}\right]$
$=0.5\times 0.5=0.25k\text{ bar }=250bar.$