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 Kif the Henry’s law constants for oxygen and nitrogen are 3.30 × 107 mm and 6.51 × 107 mm respectively, calculate the composition of these gases in water.

Thursday, 2 May 2013

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 Kif the Henry’s law constants for oxygen and nitrogen are 3.30 × 107 mm and 6.51 × 107 mm respectively, calculate the composition of these gases in water.
Solution
Given that
KH for O2  =3.30 × 107 mm Hg
KH for N2  =6.51 × 107 mm Hg

Percentage of oxygen (O2) = 20 %
Percentage of nitrogen (N2)= 79%
Total pressure = 10 atm,
1atm = 760 mm Hg so  we get
Total pressure = 10 × 760 = 7600 mm Hg
The partial pressure of oxygen
= 1520 mm Hg
The partial pressure of nitrogen
= 6004 mmHg
Use the formula of Henry law(KH is given in problem )
PA = KH  ×  XA
Molar fraction of oxygen  XO2 = PO2 / KH
XO2 = 1520 /(3.30 × 107)  = 4.61 × 10 – 5  
Similarly for nitrogen
XN2 = 6004 /(6.51 × 107)  = 9.22 × 10 – 5  
Answer
Mole fractions of oxygen = 4.61 ×10−5
Mole fraction of nitrogen= 9.22 ×10−5

2 comments:

  1. This is really an interesting topic. Congratulations to the writer. I'm sure a lot of readers having fun reading your post. Hoping to read more post from you in the future. Thank you and God bless!


    Rica
    www.imarksweb.org

    ReplyDelete
  2. As a person you should know what are your priorities and goals so that it is easier for you to determine and decide when is the time to give up or go on.
    Thanks for sharing such a wonderful article, I hope you could inspire more people. Visit my site for an offer you wouldn't want to refuse.

    n8fan.net

    www.n8fan.net

    ReplyDelete