A zinc ore gave CO₂ on treatment with a dilute acid. Identify the ore and write its chemical formula.

80 you can buy solid air-freshners in shops. Do you think these substance are ionic or covalent? why ? 81 Give the formulae of the chlorides of the elements X and Y having atomic numbers of 3 and 6 respectively.

Will the properties of two chlorides be similar or different? Explain your answer.

2 What chemical process is used for obtaining a metal from its oxide? 3 State two ways to prevent the rusting of iron.