Question

Use graham's law to calculate how much faster fluorine gas, f2 , will effuse than chlorine gas,br2, will the molar mass of f2=38.0; the molar mass of br2=160

Answer 1

    Fluorine gas   effuses 1.37  times faster than  chlorine  gas

   calculation
Rate  of  F2/rate  of Cl2  =√  molar mass    Cl2 /  molar mass F2
rate  of  F2/Rate of Cl2  = √1.868

rate  of  F2/rate of Cl2 =√  71/38    = 1.37   times faster than chlorine

Answer 2

Answer: The fluorine gas will effuse 2.05 times faster than bromine gas.

Explanation:

To calculate the rate of diffusion of gas, we use Graham's Law.

This law states that the rate of effusion of gas is inversely proportional to the square root of the molar mass of that gas. The equation given by this law follows:

$\text{Rate of diffusion}\propto \frac{1}{\sqrt{\text{Molar mass of the gas}}}$

We are given:

Molar mass of Fluorine = 38 g/mol

Molar mass of Bromine = 160 g/mol

By taking their ratio, we get:

$\frac{Rate_{F_2}}{Rate_{Br_2}}=\sqrt{\frac{M_{Br_2}}{M_{F_2}}}$

$\frac{Rate_{F_2}}{Rate_{Br_2}}=\sqrt{\frac{160}{38}}\\\\\frac{Rate_{F_2}}{Rate_{Br_2}}=2.05\\\\Rate_{F_2}=2.05\times Rate_{Br_2}$

Hence, the fluorine gas will effuse 2.05 times faster than bromine gas.