Question

There are different types of chemical reactions occurring around us or being carried out for the benefit of mankind, e.g. combination reactions, decomposition reactions, displacement reactions, precipitation reactions, reduction-oxidation (redox) reactions, photochemical reactions etc. Now answer the following questions:
i. Combustion of coke is a combination reaction. CO2 is not a pollutant. Then why is combustion of coke harmful?
ii. Which reaction followed by two combination reactions is involved in white washing of walls?

iii. Give one use of tin plating in daily life.

iv. How photochemical reactions have played an important role in photography?



pls ans these questions....

Answer 1

Answer:

1. CO2 is not a pollutant when used in a limited amount. But when combustion of coke takes place in an excess amount, then it produces a poisionous gas carbon monoxide instead of CO2, which is very harmful not only to the environment but also for the living beings. This is the reason that combustion of coke is harmful.
2. A solution of slaked lime produced by the reaction is used for white washing walls. Calcium hydroxide reacts slowly with the carbon dioxide in air to form a thin layer of calcium carbonate on the walls. Calcium carbonate is formed after two to three days of white washing and gives a shiny finish to the walls
3. .The tin plating process is used for various purposes,but the most common use of tin plating is to produce a corrosion proof metal surface which is very useful in our daily lifestyle. The tin plated corrosion resistance is effective,cheap and light weight which is ideal for daily usage.
4. Photography involves a photochemical process which converts silver bromide to metallic silver by the action of photochemical reaction. Silver bromide is used as an emulsion which develops a photographic image. On exposure to light silver bromide is decomposed to metallic silver and it preserves the photographic image
5. Explanation:

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