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Write answer to the following. Explain the similarity and difference in two events, namely adding NaOH to water and adding CaO to water. - Science and Technology 1

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प्रश्न

Write the answer to the following.

Explain the similarity and difference in two events, namely adding NaOH to water and adding CaO to water.

संक्षेप में उत्तर

उत्तर

Chemical equations involved:
1) \[\ce{NaOH(s)+H2O(l)->{Na}^+_{(aq)} + OH^-_{(aq)} + \triangle (HEAT)}\]
2) \[\ce{CaO(s) + H2O(l) ->Ca(OH)2(aq) + \triangle(HEAT)}\]
Similarities:
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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अध्याय 3: Chemical reactions and equations - Exercise [पृष्ठ ४५]

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बालभारती Science and Technology 1 [English] 10 Standard SSC Maharashtra State Board
अध्याय 3 Chemical reactions and equations
Exercise | Q 2. e. | पृष्ठ ४५

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        Redox

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