Consider a container with a volume of 0.02 m3 that holds a gas at a temperature of 500 K. The gas has a molecular weight (Mm) of 28 g/mol. Calculate the root mean square velocity (vrms) of the gas molecules and the kinetic energy per mole of the gas.
6217.5 J/mol
5417.6 J/mol
4961.2 J/mol
7541.6 J/mol
Given data: Volume of container (V ) = 0.02 m3
Temperature (T) = 500 K
Molecular weight (Mm) = 28 g/mol
Boltzmann constant (k) = 1.38 × 10−23 J/K Avogadro’s number (NA) = 6.022 × 1023 mol−1
Step 1: Convert the molecular weight to kg/mol: Mm = 28 g/mol = 28 × 10−3 kg/mol
Step 2: Calculate the molar gas constant (R) using the Boltzmann constant (k) and Avogadro’s number (NA):
R = k × NA = 1.38 × 10−23 × 6.022 × 1023 = 8.31 J/(mol K)
Step 3: Calculate the root mean square velocity (vrms) using the formula:
Substitute the given values and solve for vrms:
Step 4: Calculate the kinetic energy per mole of the gas (KE) using the formula:
Substitute the given values and solve for KE: