(a) List two substances that can be used in the laboratory to
(i) dry hydrogen;
(ii) remove carbon (IV) oxide from a sample of air;
(iii) convert hot copper (II) oxide to copper;
(iv) prepare zinc chloride by the action of dilute HCI.

(b)(i) Name two alloys which contain lead.
(ii) State and explain what is observed on bubbling H\(_2\)S into a solution of Pb(NO)\(_2\).
(iii) A metal M exists as a silvery white solid at temperatures above 18°C and as a grey solid below 18°C.
I. name the phenomenon exhibited by M.
II. What term is used to describe the temperature given as 18°C in this case?

(c)(i) Write an equation for the action of heat on each of the following compounds:
I. AgNO\(_3\)
II. (NH4)\(_2\)CO\(_3\).

(ii) Copy and complete the table below

Metal	Name of main ore	Method of extraction	One major use Haematite
—	Haematite	—	—
—	—	Electrolysis of molten oxide	—

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