Match the atomic number $4, 14, 8, 15 \mathrm{and} 19$ with the following:

A solid non-metal of valency 3.

A gas of valency 2.

Match the atomic number 4, 14, 8, 15 and 19 with the following:

A metal of valency 1.

Match the atomic number $4, 14, 8, 15, \mathrm{and} 10$ with the following:

A non-metal of valency $4$.

Explain the reason:

Ionic compounds are solids with high melting points.

Explain the reason:

Solid ionic compounds do not conduct electricity but their water solution do.

An element X has electronic configuration 2, 8, 8, 1.

Write the symbol for the ion of X.

An element X has electronic configuration 2, 8, 8, 1.

State whether element X is expected to have oxidising or reducing properties. Give reason.