Simple molecular structures

2 marks · Normal

Explain why substances with simple molecular structures do not conduct electricity, even when melted.

Work this out on paper, then compare with the answer and worked solution below. With a free account you can submit written answers for marking.

Show answer

Must show: molecules do not have free electrons or ions, no mobile charge carriers present

Also accept: Their particles are neutral; no charged particles free to move,

Common mistakes: thinking molecules split into ions on melting

Show mark scheme and worked solution

Marking points

B1 · 1 mark · State there are no free electrons or ions.

B2 · 1 mark · Explain that there are no mobile charge carriers to conduct electric current.

Worked solution

Substances with simple molecular structures do not conduct electricity because their molecules do not have free electrons or ions. There are no mobile charge carriers, so no electric current can flow.