Question

a sample of H2 is collected over water such that the combined hydrogen water vapor sample is held at a pressure of one standard atmosphere. what is the partial pressure of the H2 if that of the water vapor is 2.5 kPa

Answer 1

Answer : The partial pressure of
`H_2` is 98.825 kPa.

Solution : Given,

Total pressure of hydrogen water vapor = 1 atm = 101.325 kPa (1 atm = 101.325 kPa)

Partial pressure of water vapor = 2.5 kPa

Dalton's law of partial pressure : It is defined as the total pressure exerted is equal to the sum of the partial pressure of individual gases.

Formula used :

`P_(Total)=\sum_(i=1)^nP_i`

`P_(Total)` = Total pressure

`P_(i)` = Partial pressure of individual gases

`P_(Total)=P_(H_2)+P_{\text{ Water vapor}}`

Now put all the given values in this expression, we get

`101.325kPa=P_(H_2)+2.5kPa`

`P_(H_2)=98.825kPa`

Therefore, the partial pressure of
`H_2` is 98.825 kPa.