The air is a mixture of a number of gases. The major components are oxygen and nitrogen with approximate proportion of 20% is to 79% by volume at 298 K. The water is in equilibrium with air at a pressure of 10 atm. At 298 K, if the Henry's law constants for oxygen and nitrogen are 3.30xx10^(7) mm and 6.51xx10^(7) mm respectively, calculate the composition of these gases in water.

The air is a mixture of a number of gases. The major components are ox

1.	The air is a mixture of a number of gases. The major components are oxygen and nitrogen with approximate proportion of 20% is to 79% by volume at 298 K. The water is in equilibrium with air at a pressure of 10 atm. At 298 K, if the Henry's law constants for oxygen and nitrogen are 3.30xx10^(7) mm and 6.51xx10^(7) mm respectively, calculate the composition of these gases in water.
Answer» Solution :Total pressure of air in equilibrium with WATER = 10 ATM As air contains `20%` oxygen and `79%` nitrogenby volume, `therefore"Partial pressure of oxygen "(p_(O_(2)))=(20)/(100)xx"10 atm = 2 atm "=2XX"760 mm = 1520 mm"` `"Partial pressure of nitrogen "(p_(N_(2)))=(79)/(100)xx"10 atm = 7.9 atm "=7.9xx"760 mm = 6004 mm"` `""K_(H)(O_(2))=3.30xx10^(7)mm, K_(H)(N_(2))=6.51xx10^(7)mm` `"Applying HENRY's law,"p_(O_(2))=K_(H)xx x_(O_(2))"or"x_(O_(2))=(p_(O_(2)))/(K_(H))=("1520 mm")/(3.30xx10^(7)" mm")=4.61xx10^(-5)` `""p_(N_(2))=K_(H)xx x_(N_(2))"or"x_(N_(2))=(p_(N_(2)))/(K_(H))=("6004 mm")/(6.51xx10^(7)" mm")=9.22xx10^(-5)`.