which statement best explains why different gases effuse at different rates?\nat a given pressure, gas…

which statement best explains why different gases effuse at different rates?\nat a given pressure, gas particles with smaller masses move faster.\nat a given pressure, gas particles with smaller masses move slower.\nat a given temperature, gas particles with smaller masses move faster.\nat a given temperature, gas particles with smaller masses move slower.
Answer
Brief Explanations:
According to Graham's law of effusion, the rate of effusion of a gas is inversely proportional to the square - root of its molar mass. At a given temperature, the average kinetic energy of gas particles is the same for all gases. Kinetic energy is related to mass and velocity by the formula $KE=\frac{1}{2}mv^{2}$. Since $KE$ is constant at a given temperature, gas particles with smaller masses must have higher velocities.
Answer:
At a given temperature, gas particles with smaller masses move faster.