Define non-metals. Give five examples of non-metals. (b) Name a non-metal which conducts electricity. (c) Name a non-metal having lustre (shining surface). (d) Name a non-metal which is extremely hard. (e) How do non-metals react with oxygen? Explain with an example. Give equation of the reaction involved. What is the nature of the product formed ? How will you demonstrate it?

• Non-metals are those which have poor conduction of electricity and they are neither malleable nor ductile

Examples: Carbon, Sulphur, Phosphorus, Silicon and oxygen.

• Carbon conducts electricity
• Iodine has shining lustre
• Carbon allotrope diamond is hard
• Non-metals react with oxygen to form acidic oxides or neutral Carbon burns in air to form carbon dioxide.

C(s) + O2(g) → CO2(g)

Product formed is acidic. When carbon dissolves in water, it forms carbonic acid and turns litmus to red.