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प्रश्न
Give reasons why copper is used to make hot water tanks and not steel (an alloy of iron).
Give reasons for the following:
To make hot water tanks, copper is used and not steel.
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उत्तर १
- Copper is a good conductor of heat and does not react with hot water; on the contrary, iron reacts with hot water.
- Iron reacts with steam to corrode the tank, whereas copper does not react with either of these substances.
- Steam has an effect on iron, while temperature fluctuations have no effect on copper.
- When hot water produces steam, iron reacts with it in the following forms:
\[\ce{\underset{Iron}{3Fe} + \underset{Water}{4H2O} -> \underset{Ferric oxide}{Fe3O4} + \underset{Hydrogen gas}{4H2↑}}\]
Therefore, copper rather than steel is used to make hot water tanks.
उत्तर २
Copper is less reactive and a better conductor of heat. It does not corrode easily, making it suitable for hot water tanks. Hence, copper is used to make hot water tanks.
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