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Question
Write the answer to the following.
Explain the similarity in two events, namely adding NaOH to water and adding CaO to water.
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Solution
When NaOH and CaO are dissolved independently in water, solid NaOH dissolves and releases heat, raising the temperature. This is an exothermic process. A significant amount of heat is released when solid CaO dissolves in water to create Ca(OH)2. Additionally, this process is exothermic. Both reactions result in a single product and are combination reactions.
\[\ce{NaOH_{(s)} + H2O -> NaOH_{(aq)} + Heat}\]
\[\ce{CaO_{(s)} + H2O -> Ca(OH)_{2(aq)} + Heat}\]
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