Amixture of h2 and water vapor is present in a closed vessel at 20°c. the total pressure of the system is 755.0 mmhg. partial pressure of water vapor at 20°c equals 17.5 mmhg. what is the partial pressure of h2? mmhg

The partial pressure of H2 is 737.47 mmHg

Explanation:

Let's apply the Ideal Gas Law to discover the total mols.

We assume that the closed vessel has 1 L of volume

P. V  = n . R . T

We should convert mmHg to atm.

760 mmHg ___ 1 atm

755 mmHg ___ (755/760) = 0.993 atm

0.993 atm . 1L = n . 0.082 L.atm/mol.K . 293 K

(0.993 atm . 1L) / ( 0.082mol.K/L.atm . 293K) = n

0.0413 mols = n

These are the total moles.

Now we can kwow the moles of water vapor, to find out the molar fraction of it.

P. V  = n . R . T

760 mmHg ___ 1 atm

17.5 mmHg ___ (17.5 mmHg / 760 mmHg) = 0.0230 atm

0.0230 atm . 1L = n . 0.082 L.atm/mol.K . 293 K

(0.0230 atm . 1L) / (0.082mol.K/L.atm . 293K)= n

9.58x10⁻⁴ mols = n

Molar fraction = mols of gas/total mols

Molar fraction water vapor = 9.58x10⁻⁴ mols / 0.0413 mols

Sum of molar fraction = 1

1 - 9.58x10⁻⁴ mols / 0.0413 mols = molar fraction H2

0.9767 = molar fraction H2

H2 pressure / Total pressure = molar fraction H2

H2 pressure / 755 mmHg = 0.9767

h2 pressure = 755 mmHg . 0.9767 = 737,47 mmHg

explanation:

two years ago, when picking flowers in the mountains back of yosemite valley, i found a book. it was blotted and storm-beaten; all of its outer pages were mealy and crumbly. the paper seemed to dissolve like the snow beneath which it had been buried, however; many of the inner pages were well preserved. and although all were more or less stained and torn, whole chapters were easily readable. this is the condition of the great open book of yosemite glaciers today; its granite pages have been torn and blurred by the same storms that wasted the castaway book.

two years ago, when picking flowers in the mountains back of yosemite valley; i found a book. it was blotted and storm-beaten, all of its outer pages were mealy and crumbly. the paper seemed to dissolve like the snow beneath which it had been buried, however, many of the inner pages were well preserved. and although all were more or less stained and torn; whole chapters were easily readable. this is the condition of the great open book of yosemite glaciers today, its granite pages have been torn and blurred by the same storms that wasted the castaway book.