Answer : The partial pressure of the hydrogen is, 705.9 mmHg
Explanation :
According to the Dalton's law of partial pressure,
[tex]P_T=P_{H_2}+P_{H_2O}[/tex]
where,
[tex]P_T[/tex] = total pressure of the gas = 729.7 mmHg
[tex]P_{H_2}[/tex] = partial pressure of the hydrogen gas = ?
[tex]P_{H_2O}[/tex] = partial pressure of the water = 23.8 mmHg (standard value)
Now put all the given values in the above expression, we get:
[tex]729.7mmHg=P_{H_2}+23.8mmHg[/tex]
[tex]P_{H_2}=705.9mmHg[/tex]
Therefore, the partial pressure of the hydrogen is, 705.9 mmHg