Give reasons
a) Coke is seldom used as a fuel.
b) We should not give Gold jewellery for polishing to goldsmith.
c) Nylon is used for making swimwear.
Answers
Answer:
a Since smoke-producing constituents are driven off during the coking of coal, coke forms a desirable fuel for stoves and furnaces in which conditions are not suitable for the complete burning of bituminous coal itself. Coke may be combusted producing little or no smoke, while bituminous coal would produce much smoke.
b In the jeweler’s shop, to polish gold jewelry it is dipped in an acid called Aqua Regia.Aqua Regia dissolves the outer layer of gold.So, the inner shiny layer is visible.As there is a loss of the outer layer there is a slight loss in its weight.
c Nylon: Because of its strength nylon is by far the most popular swimwear fabric. Swimwear made out of nylon is very lightweight and dry fast, which makes it ideal for aquatic use.