heavy
Give reasons for the following:
(a) Solid sodium chloride does not conduct electricity while sodium chloride
solution conducts.
(b) It is not safe to carry out electrical repairs outdoors during a
downpour.
(c) To carry out electrolysis of water, a few drops of sulphuric acid are
(carefully) added to the water.
(d) Kitchen gas burners are often coated with chromium.
Answers
Answer:
[A] In the solid state, ionic compounds such as sodium chloride have their ions fixed in position and therefore these ions cannot move so solid ionic compounds cannot conduct electricity. However in the molten state, ions in ionic compounds are free to flow and therefore molten sodium chloride can conduct electricity.
[B] It is not safe to repair electrical appliances outdoors during heavy downpour. This is because rain water contains dissolved salts. Therefore, rain water can conduct electricity. The electrician may get electrical shocks while working outdoors during rain.
[C] To increase the conductivity of water a few drops of sulphuric acid is added . Being a strong acid it can ionize completely to release H+ ions. These H+ ions are responsible for the conduction of electricity. To carry out electrolysis in water,a few drops of sulphuric acid is added to the water.
[D] Chromium is coated in kitchen gas burners because it prevents corrosion. The hardness of the gas burners is also increased by giving a coat of chromium or hard chrome plating them. Besides, they grow the aesthetic value and provide a shiny look.