# In a mixture of N2 and O2 gases, the mol fraction of N2 is found to be 0.700. The total pressure of the mixture is 1.42 atm. What is the partial pressure of O2 in the mixture? We have `N_2` and `O_2` in the gas mixture. Mole fraction of `N_2` is 0.7

`X_(N_2) = 0.7`

Since mole fraction of both gasses add up to 1;

`X_(O_2) = 1-0.7 = 0.3`

Total pressure `(P_T) = 1.42atm`

Partial pressure = (mole fraction)`xx` (total pressure)

`P_(O_2) = X_(O_2)xxP_T`

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We have `N_2` and `O_2` in the gas mixture. Mole fraction of `N_2` is 0.7

`X_(N_2) = 0.7`

Since mole fraction of both gasses add up to 1;

`X_(O_2) = 1-0.7 = 0.3`

Total pressure `(P_T) = 1.42atm`

Partial pressure = (mole fraction)`xx` (total pressure)

`P_(O_2) = X_(O_2)xxP_T`

`P_(O_2) = 0.3xx1.42 = 0.426atm`

So the partial pressure of `O_2` is 0.426atm.

Assumption

Both gasses act as ideal gasses.

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