Explain why:
(1) In the electrolysis of alumina using the Hall Heroult’s process the electrolyte.
(2) Iron sheets are coated with zinc during galvanization.
1) An electrolyte is covered with powdered coke to prevent heat loss from the molten electrolyte.
2) Iron sheets are coated with zinc by galvanisation to prevent rusting of iron sheets.
Q7. (a) The following question is pertaining to the laboratory preparation of hydrogen chloride gas:
(i) Write the equation for its preparation mentioning the condition required.
(ii) Name the drying agent used and justify your choice.
(iii) State a safety precaution you would take during the preparation of hydrochloric acid.
Give appropriate scientific reason for the following statement:
Zinc oxide is reduced to zinc by using carbon monoxide, but aluminium oxide cannot be reduced by a reducing agent.
For each of the substance listed below. Describe the role played in the extraction of aluminium.
(1) Cryolite:
(2) sodium hydroxide
(3) Graphite
The acid on mixing with silver nitrate solution produces a white precipitate which is soluble in excess ammonium hydroxide ?
Given balanced chemical equation for each of the following:
Lab preparation of ammonia using an ammonium salt.
Identify the acid which matches the following description:
The acid which is used in the preparation of a non-volatile acid.
Q.1 (b) Choose the most appropriate answer for the following:
(iii) This is not an alloy:
A) brass
B) bronze
C) solder
D) Duralumin
State one relevant observation for the following:
when ammonia gas is burnt in an atmosphere of excess oxygen.
