2.2 - Simple molecules

Question 1

How are the atoms within a molecule held together?

Answer 1

Strong covalent bonds

Question 2

Why do simple molecules have little attraction for each other?

Answer 2

The strong covalent bonds in the molecule act only between atoms within the molecule

Question 3

Why can’t simple molecules conduct electricity?

Answer 3

Molecules have no overall charge and so cannot carry electrical charge

Question 4

What are intermolecular forces?

Answer 4

The forces of attraction between molecules

Question 5

Why do substances made of small molecules have low melting and boiling points?

Answer 5

The intermolecular forces (forces of attraction between molecules) are weak, and are overcome when a molecular substance melts or boils. This means that substances made of small molecules have low melting and boiling points

Question 6

Why are substances with small molecules gases at room temperature?

Answer 6

The smallest molecules, like H2, Cl2, and CH4, have the weakest intermolecular forces and are therefore gases at room temperature

Question 7

Why are substances with large molecules more likely to be liquids or solids at room temperature?

Answer 7

They have greater intermolecular forces, so may be liquids or solids with low melting points at room temperature