QCE Chemistry Unit 2 Topic 1 Review

Which molecular shape is predicted for NH₃ using VSEPR theory?

• Linear

• Trigonal planar

• Pyramidal

• Tetrahedral

Which factor most strongly determines whether a molecule is polar?

• Atomic radius

• Symmetry of molecular shape

• Molar mass

• Number of protons

Which intermolecular force is the weakest?

• Dispersion forces

• Dipole–dipole forces

• Hydrogen bonding

• Ionic bonding

Which substance has the highest boiling point?

• CH₄

• NH₃

• CO₂

• H₂

Water has an unusually high boiling point due to:

• Strong dispersion forces

• Metallic bonding

• Hydrogen bonding

• Dipole-dipole forces

In paper chromatography, the mobile phase is usually:

• The paper

• The solvent

• The ink or dye sample

• The filter funnel

A compound travelled 2.4 cm up a chromatography paper while the solvent travelled 6.0 cm. Its Rf value is:

• 0.24

• 0.40

• 0.60

• 2.50

Substances separate in chromatography mainly because of:

• Density differences

• Different interactions with mobile and stationary phases

• Differences in colour intensity

• Differences in mass number

At STP, one mole of any ideal gas occupies:

• 11.2 L

• 22.4 L

• 1.00 L

• 24.5 L

Which equation represents the ideal gas law?

• P = kT

• PV = nRT

• P = V/T

• n = M/m