(b) Haematite; Iron (III) oxide, Fe2O3
(c) Zinc sulphide (zinc blende ore) is strongly heated in air (roasted), it forms zinc oxide and sulphur dioxide. This process is called roasting.
Then, zinc oxide is heated with carbon to form zinc metal. This process is termed as reduction.
(d) The galvanized iron object remains protected against rusting even if a break occurs in the zinc layer because zinc is more easily oxidised than iron. Hence, the zinc continues to corrode but iron object does not corrode or rust.