Bonding, structure and properties | Starter Quiz | Oak National Academy

Why do atoms form bonds?

• To increase their energy.

• To decrease their temperature.

• To attain a stable electron configuration.

• To increase their size.

Answer explanation

Atoms form bonds to attain a stable electron configuration, similar to that of noble gases.

Match the type of bonding to its description:

• covalent

• Electrons are shared between atoms.

• metallic

• Electrons are delocalised among a lattice of metal ions.

• ionic

• Electrons are transferred, so charged ions, not atoms, are bonded.

Answer explanation

Covalent bonding – electrons are shared between atoms to fill their outer shells. Ionic bonding – electrons are transferred to form charged ions which then bond. Metallic - outer shell electrons are delocalised and move freely among metal ions.

What type of bonding can be found between non–metal atoms?

• covalent

• ionic

• metallic

Answer explanation

Covalent bonds form when non–metal atoms share electrons.

From the diagrams below, select the image depicting a substance with ionic bonding.

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• 
• 

Answer explanation

Ionic bonding is the bonding between oppositely charged ions (both positive and negative).

What is a key characteristic of metallic bonding?

• The sharing of electron pairs equally between atoms.

• The complete transfer of electrons between atoms to form charged ions.

• The pooling of electrons in a 'sea' around a network of ions.

• The presence of a dipole moment due to unequal electron sharing.

Answer explanation

Outer shell electrons form a 'sea' of delocalised electrons around regularly ordered positive metal ions. This electrostatic attraction is known as metallic bonding.

Which of the following substances would you expect to conduct electricity when solid?

• sodium chloride

• iron

• carbon dioxide

• graphite

Answer explanation

Ionic substances like sodium chloride will only conduct electricity when molten or in aqueous solution. Metals like iron and some non–metals like graphite have delocalised electrons that can carry a charge.