# Problem: Elemental analysis of the unknown gas from Part A revealed that it is 30.45% N and 69.55% O by mass. What is the molecular formula for this gas?Express your answer as a chemical formula.The rate of effusion of a gas, r, is inversely proportional to the square root of its molar mass, M. The relative rate of two different gases is expressed asr1r2=M2M1where r1 and r2 are the effusion rates of two gases and M1 and M2 are their respective molar masses.

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Elemental analysis of the unknown gas from Part A revealed that it is 30.45% N and 69.55% O by mass. What is the molecular formula for this gas?

The rate of effusion of a gas, r, is inversely proportional to the square root of its molar mass, M. The relative rate of two different gases is expressed as

$\frac{{\mathbf{r}}_{\mathbf{1}}}{{\mathbf{r}}_{\mathbf{2}}}\mathbf{=}\sqrt{\frac{{\mathbf{M}}_{\mathbf{2}}}{{\mathbf{M}}_{\mathbf{1}}}}$

where r1 and r2 are the effusion rates of two gases and M1 and M2 are their respective molar masses.