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.
$(i)$ The substance $'X'$ is calcium oxide. Its chemical formula is $CaO$.
$(ii)$ Calcium oxide reacts vigorously with water to form calcium hydroxide (slaked lime).
$\underset{\begin{smallmatrix}
Calcium\text{ }oxide \\
\left( Quick\text{ }lime \right)
\end{smallmatrix}}{\mathop{Ca{{O}_{(s)}}}}\,+\underset{Water~}{\mathop{{{H}_{2}}{{O}_{(l)}}}}\,\to \underset{\begin{smallmatrix}
~Calcium\text{ }hydroxide~ \\
\text{ }\left( Slaked\text{ }lime \right)
\end{smallmatrix}}{\mathop{Ca{{(OH)}_{2\left( aq \right)}}}}\,$
Write the balanced chemical equation for the following and identify the type of reaction in each case.
$(a)$ Potassium bromide $(aq)$ $+$ Barium iodide$(aq)$ $\rightarrow$ Potassium iodide$(aq)$ $+$ Barium bromide$(s)$
$(b)$ Zinc carbonate$(s)$ $\rightarrow$ Zinc oxide$(s)$ $+$ Carbon dioxide$(g)$
$(c)$ Hydrogen$(g)$ $+$ Chlorine$(g)$ $\rightarrow$ Hydrogen chloride$(g)$
$(d)$ Magnestum $(s)$ $+$ Hydrochloric acid$(aq)$ $\rightarrow$ Magnesium chloride$(aq)$ $+$ Hydrogen $(g)$
Write one equation each for decomposition reactions where energy is supplied in the form of heat, light or electricity.
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.
Why are decomposition reactions called the opposite of combination reactions? Write equations for these reactions.
What is the difference between displacement and double displacement reactions ? Write equations for these reactions.