Identify the following oxides with neutral, acidic, basic and amphoteric oxides.
i) Al₂O₃  ii) MgO  iii) SO₂  iv) CO;  v) Na₂O  vi) N₂O  vii) ZnO  viii) CO₂  ix) SO₃ x) CaO.

2 Name one non-metal and one metal, which are in liquid state at room temperature. 3 Give reasons for the following
i) Zinc oxide is considered an amphoteric oxide.
ii) Non-metals in general do not displace hydrogen from dilute acids.
iii) Metals conduct electricity. 5 By what processes do you concentrate the following ores:
i) PbS(galena)
ii) Fe₂O₃(haematite)
iii) Al₂O₃.2H₂O (bauxite). 6 Why is that iron does not occur as a metal in the crust of the earth? What are the common compound forms in which iron occurs? Which of these is more often used for extracting iron? Why are carbon and limestone mixed with iron ore before feeding it into the blast furnace? Write the chemical equations for the reduction step and the slag formation step.