Which of the following are true statements ?

Question

a) For a liquid to have a vapor pressure, rate of condensation must be greater than rate of evaporation.

b) Substances with large molar masses have relatively low vapor pressures.

c) An increase in temperature will increase the vapor pressure of a liquid

d) Temperature changes during a phase change.

e) For ice to float in water, it's density must be less than that of water.

Answer 1

a false
b don't know
c true
d true
e true

Answer 2

a) False
b) ??
c)True
d)False, you can just change pressure and keep the temperature constant
e)True

Answer 3

c and e. b is generally true, but there are exceptions.