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प्रश्न
Give scientific reasons.
While preparing dil. Sulphuric acid from concentrated conc. sulphuric acid in the laboratory the concentrated sulphuric acid is, add slowly to water with constant stirring.
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उत्तर
i. This is exothermic process.
ii. if we poured conc. sulphuric acid speedily in a water. Water gets evaporated instantaneously and very large amount of heat is liberated which may cause an accident.
iii. to avoid this, and only small amount of heat is liberated at a time it added slowly to water with constant stirring
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