Unit 3 Part 2 Practice Test

QT: 3.2

Which of the following statements are both true and explained by the kinetic molecular theory of gas?

I) Gas molecules typically have velocities of hundreds of meters per second at room temperature.

II) There is an inverse square root relationship between temperature and gas velocity.

III) The smaller the molecular weight of a gas, the faster it diffuses.

IV) Intermolecular attractions between gas molecules reduce the effective pressure of the system.

•   I and III only

•   I, II, III, and IV

•   I, II, and III only

•   I only

QT: 3.10

Which of the sets of conditions listed below ALL contribute to an increase in gas non-ideality?

•   low pressures, low temperatures, and small volumes

•   low pressures, high temperatures, and large volumes 

•   high pressures, low temperatures, and small volumes 

•   high pressures, high temperatures, and large volumes

QT: 3.11

Rank the following gases in order of increasing non-ideality due to intermolecular interactions:

HCl, CF₄, N₂, He

•   He < N₂ < CF₄ < HCl 

•   HCl < CF₄ < N₂ < He

•   He < N₂ < HCl < CF₄

•   CF₄ < HCl < N₂ < He

QT: 3.12

Which of the following compounds both form intramolecular bonds that exceed 500 kJ/mole?

•   NaCl, Cl₂

•   N₂, CaO 

•   CaO, CCl₄

•   CH₄, N₂

QT: 3.12

Which of the following is the strongest intermolecular force?

•   Covalent bonding

•   Hydrogen bonding

•   Dipole-dipole

•   Dispersion forces

QT: 3.13

Which of the following statements about intermolecular forces is correct?

•   Polar compounds are not able to form dispersion forces

•   Compounds exhibiting only dispersion forces are not able to form solids

•   In non-polar molecules, dispersion forces result from the momentary polarization of the electron cloud 

•   Permanent dipoles form only in molecules with symmetrical geometries

QT: 3.13

Which of the following statements about permanent dipoles is true?

•   They can occur in non-polar molecules

•   They are more important/significant than dispersion forces in large molecules

•   They occur in asymmetrical molecules

•   They are larger than hydrogen bonds

QT: 3.14

Which figure best describes the hydrogen bonding between two water molecules?

• 
• 
• 
• 

QT: 3.14

Which of the following is NOT a characteristic of a hydrogen bond?

•   It can occur when hydrogen is covalently bound to very electronegative elements like F, Br, Cl, and I 

•   It is weaker than a covalent bond

•   It is stronger than dipole-dipole interactions of covalently-bonded asymmetrical molecules like CF₃Cl

•   It is responsible for the unusual physical properties of water

QT: 3.15

Identify ALL the kinds of intermolecular forces that might arise between molecules of CH₃OH.

•   Dispersion forces and dipole-dipole

•   Hydrogen bonding only

•   Dipole-dipole and hydrogen bonding

•   Dispersion forces, dipole-dipole, and hydrogen bonding