Question
Chemistry Question on Solutions
When a gas is bubbled through water at 298K, a very dilute solution of the gas is obtained. Henry?s law constant for the gas at 298K is 100kbar. If the gas exerts a partial pressure of 1bar, the number of millimoles of the gas dissolved in one litre of water is
A
0.555
B
5.55
C
0.0555
D
55.5
Answer
0.555
Explanation
Solution
Answer (a) 0.555
According to the Question:-
Pgas=(KH)Xgas
1=(100×103)Xgas
Xgas=1×10−5
ngas+nwaterngas=1×10−5
ngas+nwater≈nwater (∵ngas<<<nwater)
1000/18ngas=1×10−5
ngas=5.556×10−4
Therefore, the number of millimoles of the gas dissolved in one litre of water is ngas=0.555