GCSE Chemistry - Properties of Simple Molecular Substances & Giant Covalent Structures #17

The video explains covalent bonds, focusing on simple molecular substances and giant covalent structures. Simple molecular substances, like chlorine, have low melting and boiling points due to weak intermolecular forces. In contrast, giant covalent structures, such as diamond and silicon dioxide, have high melting and boiling points due to strong covalent bonds. The video also highlights that simple molecular substances do not conduct electricity, while graphite, a giant covalent structure, is an exception.

What type of bonds hold the atoms together in simple molecular substances?

• Hydrogen bonds

• Ionic bonds

• Metallic bonds

• Covalent bonds

Why do simple molecular substances generally have low boiling points?

• They are composed of large molecules.

• They have strong covalent bonds within molecules.

• They have weak intermolecular forces between molecules.

• They have free electrons that move easily.

As you move down the group of halogens, what happens to the boiling points?

• They fluctuate randomly.

• They decrease because molecules get smaller.

• They remain constant.

• They increase because molecules get larger.

Which of the following is a property of giant covalent structures?

• They have high melting and boiling points.

• They are composed of small molecules.

• They conduct electricity well.

• They have low melting points.

Which giant covalent structure is an exception in terms of electrical conductivity?

• Graphite

• Diamond

• Silicon dioxide

• Ammonia