What does one mean by exothermic and endothermic reactions ? Give examples.

Write the balanced chemical equations for the following reactions.

$(a)$ Calcium hydroxide $+$ Carbon dioxide $\rightarrow$ Calcium carbonate $+$ Water

$(b)$ Zinc $+$ Silver nitrate $\rightarrow$ zinc nitrate $+$ Silver

$(c)$ Aluminium $+$ Copper chloride $\rightarrow$ Aluminium chloride $+$ Copper

$(d)$ Barium chloride$+$ Potassium sulphate $\rightarrow$ Barium sulphate $+$ Potassium chloride

Give an example of a double displacement reaction other than the one given in image.

In the refining of silver, the recovery of silver from silver nitrate solution involved displacement by copper metal. Write down the reaction involved.

Balance the following chemical equations.

$(a)$ $HNO _{3}+ Ca ( OH )_{2} \longrightarrow Ca \left( NO _{3}\right)_{2}+ H _{2} O$

$(b)$ $NaOH + H _{2} SO _{4} \longrightarrow Na _{2} SO _{4}+ H _{2} O$

$(c)$ $NaCl + AgNO _{3} \longrightarrow AgCl + NaNO _{3}$

$(d)$ $BaCl _{2}+ H _{2} SO _{4} \longrightarrow BaSO _{4}+ HCl$