Advertisements
Advertisements
Question
Name the gas in air which tarnishes silver articles slowly.
Solution
Hydrogen sulphide gas in the air tarnishes silver articles slowly. Silver reacts with hydrogen sulphide gas in the air and forms a thin black layer of silver sulphide (Ag2S) on it. Therefore, silver jewellery or ornaments become dull due to the formation of silver sulphide coating on their surface.
APPEARS IN
RELATED QUESTIONS
In the extraction of aluminium: Why is it necessary to replace anodes time to time?
Define the terms gangue.
Which of the following reactants are used to carry out the thermite reaction required for welding the broken railway tracks?
(a) Al2O3 + Fe
(b) MnO2 + Al
(c) Fe2O3 + Al
(d) Cu2O + Fe
During galvanisation, iron metal is given a thin coating of one of the following metals. This metal is:
(a) chromium
(b) tin
(c) zinc
(d) copper
Give the principles of the hydrolytic method.
Which method of refining is used to get 99.8% pure aluminium?
Aluminium oxide is _______ oxide.
Write the name.
The process of extraction of aluminium from alumina-
Write the molecular formulae of the following compound.
Sodium aluminate
Why should the metal sulphides and carbonates be converted to metal oxides in the process of extraction of metal from them?