For a gas with molar mass M at temperature T, what is the relationship between R
Practice Questions
Q1
For a gas with molar mass M at temperature T, what is the relationship between RMS speed and molar mass?
v_rms is directly proportional to M
v_rms is inversely proportional to M
v_rms is independent of M
v_rms is proportional to M^2
Questions & Step-by-Step Solutions
For a gas with molar mass M at temperature T, what is the relationship between RMS speed and molar mass?
Correct Answer: RMS speed is inversely proportional to the square root of molar mass.
Step 1: Understand that RMS speed (v_rms) is a measure of the average speed of gas particles.
Step 2: Know that the formula for RMS speed is v_rms = sqrt((3RT)/M), where R is the gas constant and T is the temperature.
Step 3: Identify that M represents the molar mass of the gas.
Step 4: Notice that in the formula, M is in the denominator under the square root.
Step 5: Realize that if M increases (the molar mass gets larger), the value of v_rms decreases because they are inversely related.
Step 6: Conclude that RMS speed is inversely proportional to the square root of the molar mass M.
RMS Speed – The root mean square speed of gas molecules, which is a measure of the average speed of particles in a gas.
Molar Mass – The mass of one mole of a substance, typically expressed in grams per mole (g/mol).
Inversely Proportional Relationship – A relationship where one quantity increases as the other decreases; in this case, RMS speed decreases as molar mass increases.
Gas Laws – The principles governing the behavior of gases, including the ideal gas law and kinetic molecular theory.