We have that the Atmospheric pressure in mm Hg
[tex]P_{N_2}=0.78*749\\\\P_{N_2}=684.22mmHg[/tex]
From the question we are told
The Hg columns in Diagram A are of equal height. If the pressure of the confined gas is 749 mm Hg, what is the atmospheric pressure in mm Hg
Generally the equation for the Moles Fraction of N is mathematically given as
[tex]Mole N=\frac{mole of NO_2}{Miles of Mixture}\\\\Moles=\frac{n_{N_2}}{n_t}[/tex]
Since Generally
Composition of N_2 in air is=\%78
[tex]n_{N_2}=78*N_a\\\\X_{N_2}=\frac{78}{100}\\\\\X_{N_2}=0.78[/tex]
Therefore
Atmospheric pressure in mm Hg
[tex]P_{N_2}=0.78*749\\\\P_{N_2}=684.22mmHg[/tex]
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