Question

Write the answer to the following.

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

Answer 1

NaOH and water do not undergo a chemical reaction. NaOH in aqueous solution is regarded as a strong alkali.

Ca(OH)₂ in aqueous solution is regarded as a weak alkali. The reaction that follows occurs

\[\ce{CaO + H2O -> Ca(OH)2 + Heat}\]