Which statement best explains why different gases effuse at different rates?
at a given pressure, gas particles with smaller masses move faster.
at a given pressure, gas particles with smaller masses move slower.
at a given temperature, gas particles with smaller masses move faster.
at a given temperature, gas particles with smaller masses move slower

What are the first two quantum numbers for the electrons located in subshell 4d? what are the first three quantum numbers for the electrons located in subshell 2s? how many electrons can be held in a sublevel l = 3? how many electrons can be held in the energy level n = 4? how many electrons in an atom can share the quantum numbers n = 4 and l = 3?