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Question
Write the answer to the following.
Explain the similarity and difference in two events, namely adding NaOH to water and adding CaO to water.
Solution
1) Both of the equations are exothermic. It means a lot of heat is evolved during the reaction.
2) Both reactions from strong basic solutions.
Differences :
1) Sodium Hydroxide is a strong base dissociates to form Na⁺ and OH⁻ ion. While Calcium oxide added water to form Calcium Hydroxide which further dissociates.
2) NaOH is a monoacidic base. and CaO is a Di-Acidic base.
3) NaOH, CaO should be added to water gradually with constant stirring. CaO on reacting with water produces a basic solution called Calcium hydroxide which is used for whitewashing and this reaction is more dangerous as compared to NaOH.
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