Solutions Question 329
Question: At $ 15{}^\circ C $ and 1 atmosphere partial pressure of hydrogen, 20 mL of hydrogen measured at STP dissolves in 1 L of water. If water at $ 15{}^\circ C $ is exposed to a gaseous mixture having a total pressure of 1500 mm of Hg (excluding the vapour pressure of water) and containing 80% hydrogen by volumne, then the volume of hydrogen measured at STP that will dissolve in 1 L of water is
Options:
A) 20.0 mL
B) 31.6 mL
C) 36.1 mL
D) 26.3 mL
Show Answer
Answer:
Correct Answer: B
Solution:
From the given data $ P_{H2}=1500\times 0.80 $ = 1200 mm of $ Hg=\frac{1200}{760} $ atmosphere =1.58 atmosphere
If’s are volumes of gas dissolved by same volume of liquid, then from Henry’s law $ \frac{V_2}{V_1}=\frac{P_2}{P_1};,or,\frac{V_2}{20}=\frac{1.58}{1.0} $ Or $ V_2=31.60mL $
