How much faster will hydrogen diffuse than chlorine?
Both chlorine (atomic mass 35.453) and hydrogen (atomic mass 1.0079) are diatomic and so their molecular masses are 70.906 (Mass 1)
and 2.0158 (Mass 2). We will assign the value of 1 (rate 1) for chlorine's rate of diffusion. We must solve for Rate 2.

We can rearrange Graham's Law:

(Rate 2)² = (Rate 1)² × Mass 1 ÷ Mass 2 then we plug in the numbers:

(Rate 2)² = 1² × 70.906 ÷ 2.0156

Rate 2 = 5.9309

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3) **
Oxygen diffuses 1.4886 times faster than chlorine. If we know (from problem #2) that the molecular mass of chlorine is 70.906, then what is the molecular mass of oxygen?

Mass 1 = (Rate 2)² × Mass 2 ÷ (Rate 1)²

Mass 1 = 1² × 70.906 ÷ 1.4886²

Mass 1 = 31.998

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4) **What is the molecular weight of a gas that diffuses 4 times slower than hydrogen?

The atomic mass of hydrogen is 1.0079 and since hydrogen is diatomic, the molecular mass of H₂ is 2.0158 (mass 1). We will give
hydrogen's diffusion rate a value of 4 (rate 1) and the rate of the other gas is simply 1 (rate 2).

We now have have to solve for Mass 2 and so we algebraically rearrange Graham's Law producing this formula:

Mass 2 = (Rate 1)² × Mass 1 ÷ (Rate 2)² then we plug in the numbers:

Mass 2 = 4² × 2.0158 ÷ 1² giving us our answer

Mass 2 = 32.253