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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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While preparing dilute sulphuric acid from concentrated sulphuric acid in the laboratory, the concentrated sulphuric acid is added slowly to water with constant stirring.
Give scientific reasons.
While preparing dilute sulphuric acid from concentrated sulphuric acid in the laboratory, the concentrated sulphuric acid is added slowly to water with constant stirring.
