Elements A, B and C have atomic numbers 11, 17 and 18. Identify which is a metal, which a non-metal and which is chemically inert, and give the formula of the compound formed between A and B.

An element has the electronic configuration 2, 8, 7. State its group, its period and whether it is a metal or a non-metal.

How does metallic character vary across a period and down a group, and why?

How does atomic size vary across a period and down a group? Give the reason in each case.

Define electron affinity and electronegativity, and state how each varies down a group.

Define ionisation potential and state how it varies across a period.

An element X has atomic number 12. Write its electronic configuration, its group and the formula of its chloride.