Question

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

	$\alpha$	$\beta$	$\gamma$	$\delta$
$K_H$	$50$	$2$	$2\times 10^{-5}$	$0.5$

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

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

Answer 1

Answer: (C)

(1) $P_{\gamma }=K_H{X}_Y$

$P_{\gamma }=2\times 10^{-15}\times \frac{55.5}{55.5+\frac{1000}{18}}$

$=2\times 10^{-5}K$ bar

$=2\times 10^{-2}$ bar

(2) $P_{\delta }=K_H{X}_8$

$P_{\delta }=0.5\times \frac{55.5}{55.5+\frac{1000}{18}}=.249K$ bar $=249$ bar

(3) On increasing temperature solubility of gases decreases

(4) $K_H\downarrow$ solubility $\uparrow$ and lowest $K_H$ is for $\gamma$