Question 9 (1 point)
Which statement describes how vapor pressure occurs?
a
Some molecules at the surface of a liquid have low enough kinetic energy to melt. These molecules exert pressure on the liquid.
b
Some molecules at the surface of a liquid have high enough kinetic energy to melt. These molecules exert pressure on the liquid.
c
Some molecules of at the surface of a liquid have low enough kinetic energy to vaporize. These molecules exert pressure on the liquid.
d
Some molecules at the surface of a liquid have high enough kinetic energy to vaporize. These molecules exert pressure on the liquid.