Answer:
[tex]P_T=504torr[/tex]
Explanation:
Hello!
In this case, since the Dalton's law states that the total pressure inside a container full of various gases is equal to the addition of the pressure of each gas, for the given mixture containing nitrogen, oxygen and helium we have:
[tex]P_T=P_{N_2}+P_{O_2}+P_{He}[/tex]
Thus, by plugging in each partial pressure, we obtain the total pressure of the mixture as shown below:
[tex]P_T=211torr+135torr+158torr\\\\P_T=504torr[/tex]
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