covalent and intermolecular quiz

How many electron lone pairs are present in the valence shell of a neutral phosphorus atom?

• 1

• 2

• 3

• 5

Neon does not take part in covalent bonding. Which of the following best explains this phenomena?

• While neon has 4 bonding electrons they are all paired which makes them unreactive.

• Neon’s first shell is completely full with a 1s² configuration which makes this element unreactive.

• Incorrect, neon will form covalent bonds with very reactive elements such as oxygen and potassium.

• Neon has 8 electrons in its valence shell which is a very stable and hence unreactive configuration.

Select the list in which all molecules have non-polar bonds.

• CH₃F, C₂H₆, C₃H₈

• H₂, H₂O₂, N₂

• O₂, F₂, S₅

• CO₂, HBr, NaOH

Which of the following molecules has trigonal planar geometry?

• CH₂O

• NH₃

• PH₃

• AsH₃

The strongest form of bonding present between molecules of fluoromethane (structure below) would be:

• Dispersion force

• Dipole-dipole interactions

• Hydrogen bonding

• Covalent

Which option correctly orders the following list of molecules from lowest boiling point to highest boiling point. The structures (not to scale) of each molecule are drawn below for your reference.

• Methane, Ethane, Ethanol, Chloroethane.

• Ethanol, Methane, Chloroethane, Ethane.

• Ethane, Ethanol, Chloroethane, Methane.

• Methane, Ethane, Chloroethane, Ethanol.

Dispersion force increases as:

• Number of electrons decreases and molecular size decreases.

• Number of electrons decreases and molecular size increases.

• Number of electrons increases and molecular size decreases.

• Number of electrons increases and molecular size increases.

Which of the following lists bonding strength from highest to lowest

• Ionic, covalent, dipole-dipole, dispersion

• Hydrogen bonding, covalent, dipole-dipole, dispersion

• Covalent, ionic, hydrogen bonding, dipole-dipole bonding

• Hydrogen bonding, dipole-dipole, metallic, dispersion

Water becomes less dense at high temperatures because:

• Extra energy stretches the covalent bonds of the water molecules.

• Extra energy starts to break the hydrogen bonding between molecules.

• Extra energy causes the nuclei of each hydrogen and oxygen atom to expand which increases the distance between molecules.

• None of the options presented in this question.

Which of the following molecules would have the most polar bond.

• BH₃

• NH₃

• PH₃

• AsH₃