Question

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

Answer 1

Explanation:

With NaOH you are only dissolving the material, whereas CaO reacts to make Ca(OH)2 . The calcium hydroxide has a lower solubility in water than NaOH and so will precipitate out.

Adding NaOH to water:

NaOH+H2O = Na+ and OH− ions. The reaction will be Exothermic, where heat will be released. Sodium hydroxide is considering a strong base and as such is able to completely and fully dissociate in aqueous solution.

Adding CaO to water: A lot of heat (exothermic reaction) is produced in the reaction, which may even cause the water to boil.