Why is respiration considered an exothermic reaction ? Explain.

Why should a magnesium ribbon be cleaned before burning in air ?

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

Write the balanced equation for the following chemical reactions.

$(i)$ Hydrogen $+$ Chlorine $\to $ Hydrogen chloride

$(ii)$ Barium chloride $+$ Aluminium sulphate $\to $ Barium sulphate $+$ Aluminium chloride

$(iii)$ Sodium $+$ Water $\to $  Sodium hydroxide $+$ Hydrogen

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 $(g)$