Question

A small amount wet of hydrogen gas can be prepared by the reaction of zinc with excess hydrochloric acid and trapping the gas produced in an inverted tube initially filled with water. If the total pressure of the gas in the collection tube is 729.7 mmHg at 25 C, what is the partial pressure of the hydrogen

Answer 1

Answer : The partial pressure of the hydrogen is, 705.9 mmHg

Explanation :

According to the Dalton's law of partial pressure,

$P_T=P_{H_2}+P_{H_2O}$

where,

$P_T$ = total pressure of the gas = 729.7 mmHg

$P_{H_2}$ = partial pressure of the hydrogen gas = ?

$P_{H_2O}$ = partial pressure of the water = 23.8 mmHg (standard value)

Now put all the given values in the above expression, we get:

$729.7mmHg=P_{H_2}+23.8mmHg$

$P_{H_2}=705.9mmHg$

Therefore, the partial pressure of the hydrogen is, 705.9 mmHg