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Question
Give scientific reason.
While preparing dilute sulphuric acid from concentrated sulphuric acid in the laboratory, the concentrated sulphuric acid is added slowly to water with constant stirring.
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Solution 1
- The preparation of dilute sulphuric acid falls into the category of an extreme exothermic process.
- During the preparation of dilute sulphuric acid, a large amount of water is taken into a glass container that is surrounded by ice. Cool it for twenty minutes. Now a small quantity of conc. H2SO4 is added slowly with stirring. Therefore, only a small amount of heat is liberated at a time. In this way, dilute sulphuric acid is prepared.
- On the other hand, in the process of dilution or conc. sulphuric acid with water, a very large amount of heat is liberated. As a result, water gets evaported instantaneously if it is poured into conc. H2SO4, which may cause an accident.
Solution 2
- This is an exothermic reaction.
- If we quickly put concentrated sulphuric acid into water. Water evaporates instantly, liberating a tremendous amount of heat that could cause an accident.
- To avoid this, a tiny amount of heat is supplied gently to water while stirring constantly.
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Give scientific reason.
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Give scientific reason.
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