Loading test…

AP Chemistry Unit 3: Intermolecular Forces and Properties

12 questions

Header banner

Unit 3: Intermolecular Forces and Properties

0 of 12 answered

~7 min left

Question 1

Which type of intermolecular force is present in ALL molecular substances?

A.Hydrogen bondingB.Dipole–dipole forcesC.London dispersion forcesD.Ion–dipole forces

Question 2

A gas occupies $3.00 L$ at $2.00 atm$ and $300 K$ . What volume will it occupy at $1.00 atm$ and $600 K$ , assuming ideal behavior?

3.00 L

6.00 L

12.0 L

1.50 L

Question 3

According to the kinetic molecular theory of gases, what happens to the average kinetic energy of gas molecules when temperature is doubled (from 300 K to 600 K)?

A.It doubles.B.It quadruples.C.It increases by

2

.D.It remains the same; only pressure changes.

Question 4

Rank these liquids in order of increasing viscosity: ethanol ( $C_{2} H_{5} OH$ ), glycerol ( $C_{3} H_{5} (OH)_{3}$ ), and hexane ( $C_{6} H_{14}$ ).

A.Hexane

<

Ethanol

<

GlycerolB.Ethanol

<

Hexane

<

GlycerolC.Glycerol

<

Ethanol

<

HexaneD.Hexane

<

Glycerol

<

Ethanol

Question 5

At constant temperature, the pressure of a fixed amount of gas is increased from $1.00 atm$ to $4.00 atm$ . By what factor does the volume change?

A.Increases by a factor of 4B.Decreases by a factor of 4C.Decreases by a factor of 2D.Remains unchanged

In-content ad

Question 6

A sample of ideal gas has a volume of $10.0 L$ at $27° C$ . At constant pressure, to what temperature (in $° C$ ) must the gas be cooled to reduce its volume to $7.50 L$ ?

- 48° C

0° C

20.25° C

- 75° C

Question 7

A 5.00-L container holds $0.500 mol$ of an ideal gas at $27° C$ . What is the pressure in atm? ( $R = 0.0821 L \cdot atm/ (mol \cdot K)$ )

0.274 atm

2.46 atm

4.93 atm

0.492 atm

Question 8

Explain why $HF$ has a much higher boiling point ( $19.5° C$ ) than $HCl$ ( $- 85° C$ ), even though HCl has the larger molar mass.

A.HF has stronger London dispersion forces because fluorine is highly electronegative.B.HF molecules engage in hydrogen bonding, a much stronger intermolecular attraction than the dipole–dipole forces in HCl.C.The H–F bond is covalent while H–Cl is ionic.D.HF has a higher molar mass than HCl.

Question 9

At $0° C$ and $1.00 atm$ , $1 mol$ of a real gas occupies a slightly smaller volume than predicted by the ideal gas law. What does this suggest about the dominant deviation at this condition?

A.Molecular volume is dominant, pushing measured volume above the ideal.B.Intermolecular attractions are dominant, pulling molecules together and reducing volume below the ideal.C.The gas molecules are moving faster than predicted by the kinetic molecular theory.D.The gas is undergoing a phase change at this condition.

Question 10

A solution is prepared by dissolving $5.85 g$ of NaCl (molar mass $58.5 g/mol$ ) in enough water to make $250 mL$ of solution. What is the molarity of NaCl?

0.100 M

0.400 M

2.50 M

0.0400 M

In-content ad

Question 11

A mixture of gas A (molar mass $4 g/mol$ ) and gas B (molar mass $64 g/mol$ ) effuses through a small orifice. According to Graham's Law, how much faster does gas A effuse compared to gas B?

A.4 times fasterB.16 times fasterC.

4 = 2

times fasterD.8 times faster

Question 12

Which of the following correctly explains why water has an unusually high surface tension?

A.Water molecules at the surface are attracted only by gravity, not by IMFs.B.Surface water molecules experience a net inward force due to extensive hydrogen bonding with interior molecules, resisting surface expansion.C.Water has a low molar mass, so surface molecules move slowly and resist disruption.D.London dispersion forces in water are exceptionally strong because of water's high electronegativity.

AP Chemistry Unit 3: Intermolecular Forces and Properties — Free with Answer Explanations | Test Practice Hub