At STP,as the Molar Mass of the Molecules That Make

Multiple Choice

At STP,as the molar mass of the molecules that make up a pure gas increases,the

A) root mean square speed of the molecules increases.
B) root mean square speed of the molecules decreases.
C) root mean square speed of the molecules remains constant.
D) root mean square speed increases to a maximum,then decreases.
E) none of the above.