Chemical Reactions and Equations question bank (Science)

Write a balanced chemical equation with state symbols for the following reactions.
$(i)$ Solutions of barium chloride and sodium sulphate in water react to give insoluble barium sulphate and the solution of sodium chloride.
$(ii)$ Sodium hydroxide solution (in water) reacts with hydrochloric acid solution (in water) to produce sodium chloride solution and water.

$A$ solution of a substance $X$ is used for whitewashing.
$(i)$ Name the substance $X$ and write its formula.
$(ii)$ Write the reaction of the substance $X$ named in $(i)$ above with water.