Review Intermolecular Forces and Vapor Pressure
I. A
sample of oxygen gas is sealed in container X. A sample
of hydrogen gas is sealed in container Z.Both samples have
the same volume, temperature, and pressure. Which
6. 4t298
statement is true?
(A) Container X contains more
(A) larger molecules
(B) a larger molecular mass
(C) stronger ionic bonds
(D) stronger intermolecular forces
gas molecules than
container Z.
@) Container X contains fewer
gas molecules than
container Z.
(C) Containers X and Zboth contain the same number of
gas molecules.
(D) Containers X and Zboth contain the same mass of gas.
Each stoppered flask below contains 2 liters ofa gas at STP.
K, the vapor pressure of HrO is less than the vapor
ofCSr. The best explanation forthis is that FI'O
pressure
has
7. Which
attractions are most prevalent between molecules
of
I{F in the liquid phase?
(A) van der Waals forces (B) hydrogen bonds
(C) molecule-ion attractions (D) ion-ion attractions
8.
Hydrogen bonds are formed between molecules when
hydrogen is covalently bonded to an element that has a
(A) small atomic radius and low electronegativity
(B) large atomic radius and low electronegativity
(C) small atomic radius and high electronegativity
(D) large atomic radius and high electronegativity
9. Which substance
(A) water
(C) propanone
10. Based on
has the lowest vapor pressure at75"C2
(B)
(D)
ethanoic acid
ethanol
intermolecular forces, which of these substances
would have the highest boiling point?
Each gas sample has the same
(A)
(A)
density
(B) mass
(C) numberofmolecules (D) numberof
atoms
J. The data table below gives the temperature and pressure
four different gas samples, each in a2-liler container.
ll.
of
Temperature and Pressure of Gas Samples
Gas
Temperature
Pressure
Sample
(10
(alm)
He
300.
1.20
Ne
300.
1.00
CO,
20a.
1.20
CHo
300.
1.00
Which two gas samples contain the same total number
of
particles?
(A) CH4 and CO,
(C) He and CO,
4.
CH4 and Ne
(c) cH4
Using your knowledge of chemistry and the information in
Reference Table H, which statement conceming propanone
and water at 50oC is true?
(A)
Propanone has a higher vapor pressure and stronger
intermolecular forces than water.
(B) Propanone has a higher vapor pressure and weaker
intermolecular forces than water.
(C) Propanone has a lower vapor pressure and stronger
intermolecular forces than water.
(D) Propanone has a lower vapor pressure and weaker
intermolecular forces than water.
t2. Which graph best represents the variation in the vapor
pressure ofwater as temperature changes?
(B) Br
(D) F
The unusually high boiling point of HrO is primarily due to
the presence
of
(A) hydrogen bonds
(B) ionic bonds
(C) van der Waals forces (D) molecule-ion attractions
o
o
6L
ol
ol
LI
OL
ol
ol
o. I
4l
rl
ol
G
He and Ne
Hydrogen bonds would be strongest between the
molecules of a compound of hydrogen and
(A) I
(c) cl
5.
(B)
(D)
(B) oz
(D) M:
He
-l
ol
cr
'..''....-*
I
Temperature
Temperature
o
0)
3.
ol
ol
ol
LI
o.l
tDL
stl
ol
o-I
rl
ol
cr
lE
r. I
ol
(E
---------|
Temperature
(c)
L
(B)
(A)
---'>
Temperature
(D)
r
1.3.
ffi,,
F$sg
+
18. The diagrams below represent an ionic crystal being
dissolved in water.
VAPOR
LIOUID A
CONTAINER
Liquid
I
is confined in a container as shown in the diagram
above. The equilibrium vapor pressure
on the
ofliquidl
ER
(A) amount of vapor in the container
(B) amount of liquid in the container
(C) temperature of liquid I
(D) size of the confining container
(A) hydrogen bond formation
@) network bond formation
(C) van der Waals attractions
(D) molecule-ion attractions
vapor pressure?
(c)
(B) 40"C
(D) 60"C
50"c
15. Water will boil at 50"C if the pressure on the surface of the
19. What is the normal boiling point of ethanoic acid?
water is
(A)
(C)
I'OLECULE\
According to the diagrams, the dissolving process takes
place by
14. At which temperature would glycerol have the highest
(A) 30'C
(A) 52.C
101.3 kPa
12 kPa
(B)
(D)
(c)
50 kPa
3 kPa
pressure is 30 kPa?
compounds.
(A) 2s"C
(c)
HF(f)
Normal
cH3F(4)
-78.6
Hct(d)
-83.7
Which compound has the strongest intermolecular forces?
Ir(/)
(c)
cH3F(/)
(B) cH3c(4
(D) HC(4
17. As the atmospheric pressure increases, the temperature at
which water boils in an open vessel
(A) decreases
(C) remains the same
(B)
increases
(B) 50.C
(D) 100"c
pressure on the gas
(A)
@)
(C)
(D)
19.4
-24.2
70.c
21. A gas is most likely to changeto the liquid phase when the
Boiling Point ('C)
cH3ct(d)
(A)
101.3.C
(B) 55"C
(D) 150"C
20. At which temperature will water boil when the external
t6. The table below shows the normal boiling point of four
Gompound
AX
::':Ifu
depends
aa
decreases and its temperature increases
decreases and its temperature decreases
increases and its temperature increases
increases and its temperature decreases
Which compound has the lowest melling point?
(A) HCI
(B) KCr
(C) NaCl
(D) Licl
23. A sample of a pure liquid is boiling in an open
vessel at a
temperature of 150oC. The atonospheric pressure is 65 kPa.
The vapor pressure ofthe liquid is
(A) 10 kPa
(C) 6s kPa
24. Which compound below has
@) ls kPa
(D) 76 kPa
the lawest boiling point at
standard pressure?
(A) NaI
(C) McIz
25. A liquid has
(B) ril
(D) Alr3
of90 kPa at7SoC
a vapor pressure
and a vapor
pressure of 120 kPa at 90oC. At standard atmospheric
pressure, the liquid will boil
(A) at 75"C
(B) above 75oC but below 90oC
(C) at 90"C
(D) above 90'C but below 100'C
26.
.
Base your answer to the following question on the number
of the substance, chosen from the table below. that best
answers that question.
(1)
(2)
(3)
(4)
tuIelthtg
Boil,ing
Substance
Peiut "K.
Point o K.
sodium chloride
helium
1,074
1
1,696
+
diamond
3,773
4,473
n3
water
29. Which formula
(A)
represents a nonpolar compound?
H :O:
;
(B)
373
(c)a
Which substance has molecular forces of attraction mainly
H :N:
b
H
(A)
1
(c)
3
(D)
27. Which of the following liquids
'Waals
has the weakest van der
forces of attraction between its molecules?
(A) K(/)
(C) Ar(/)
28. Argon has
I
H
H :C:
@) Ne@
(D) He(z)
a
LHJ
H
(B) 2
(D) 4
f H l+
IHItnt-t
due to van der Waals forces?
H
;;
higher boiling point than neon because argon
has
(A)
(B)
(C)
(D)
fewer electrons in its 2nd principal energy level
more electrons in its outermost principal energy level
weaker intermolecular forces of attraction
stronger intermolecular forces of attraction
30. Which substance
(A) CHo
has the highest normal
(c) caHs
melting point?
(B) czl{i
(D) C4Hro
31. As the distance between two bromine molecules
increases,
the magnitude of the existing van der Waals forces between
them
(A) decreases
(C) remains the same
At 25oC, F, is
a gas but
(B)
increases
I, is a solid. This
is most likely due
to the fact that
(A) Fz is a dipole but I, is not
(B) I, is a dipole but F, is not
(C) Fz molecules have stronger intermolecular
atlractions
(D) I, molecules have stronger intermolecular
attractions
JJ.
Which formula represents a polar molecule containing
polar covalent bonds?
(A) Hro
(C) NaCl
(B) CO2
(p) Cl"