Freon-12, CF₂Cl₂, which has been widely used in air conditioning systems, is considered a threat to the ozone layer in the stratosphere. Calculate the root-mean-square velocity of Freon-12 molecules in the lower stratosphere where the temperature is -65$\degree$C.

Question

Quizplus · Accepted Answer

The root-mean-square velocity of a gas molecule can be calculated using the following equation:

vrms = sqrt(3kT/m)

where k is the Boltzmann constant, T is the temperature in Kelvin, and m is the mass of the molecule.

First, we need to convert the temperature from Fahrenheit to Kelvin:

T = (°F + 459.67) × 5/9
T = (-65 + 459.67) × 5/9
T = 210.68 K

The molar mass of Freon-12 (CF2Cl2) is 120.91 g/mol, which is equivalent to 0.12091 kg/mol.

Now we can use the above equation to calculate vrms:

vrms = sqrt(3kT/m)
vrms = sqrt(3(1.38e-23 J/K)(210.68 K)/(0.12091 kg/mol)/(6.022e23/mol))
vrms = 210.4 m/s

Therefore, the answer is C, 210 m/s.

Freon-12, CF2Cl2, Which Has Been Widely Used in Air Conditioning °\degree°

Freon-12, CF₂Cl₂, Which Has Been Widely Used in Air Conditioning $\degree$