Liquids Homework
11.37 c) The weaker the IMFs, the higher the vapor pressure since more liquid molecules can overcome
the attractive forces and become a gas before dynamic equilibrium is achieved.
d) The higher the temperature, the higher the vapor pressure since more molecules have enough energy
to overcome the attractive forces to become a gas before dynamic equilibrium.
11.38 a) The vapor pressure of a liquid is the pressure that the gas above a liquid in a closed container
exerts after dynamic equilibrium.
b) The boiling point depends on pressure because the vapor pressure has to be equal to the atmospheric
pressure so the bubbles can form and rise to the top.
11.39 a) Since PCl3 is more volatile it will evaporate or boil first. Therefore AsCl3 has the stronger IMFs
since it takes more energy to overcome the attraction.
b) PCl3 will evaporate at a faster rate leaving more gaseous molecules when dynamic equilibrium is
reached so it will have a higher vapor pressure.
c) AsCl3 will boil at a higher temperature since it has the stronger IMFs (I knew that because it said AsCl3
was less volatile so it does not overcome attraction as easily).
11.40 Increasing volatility = decreasing IMF strength
CH4
LDF
16.0g
CBr4
LDF
331.6g
CH2Cl2
DDF
CH3Cl
DDF
CHBr3
DDF
CH2Br2
DDF
*The rest should be ranked on difference in
electronegativity but we just cannot do this one
with our knowledge
11.41 a)Since both are boiling, they must be at the same temperature because once boiling begins, the
energy is used to weaken IMFs instead of raise the temperature
11.44 a)
1.4 atm X
10.7 a) LDF
b)LDF c)LDF
10.9 a) Yes
c)no
d)no
760 mmHg
1 atm
= 1064mmhg
d)LDF e)HBF h)DDF i)LDF
approx. 110oC