Question

Write the balanced chemical equation for the following and identify the type of reaction in each case:

(a) Potassium bromide(aq) + Barium iodide(aq) $\to$ Potassium iodide(aq) + Barium bromide(s)

(b) Zinc carbonate(s) $\to$ Zinc oxide(s) + Carbon dioxide(g)

(c) Hydrogen(g) + Chlorine(g) $\to$ Hydrogen chloride(g)

(d) Magnesium(s) + Hydrochloric acid(aq) $\to$ Magnesium chloride(aq) + Hydrogen(g)

Answer 1

(a) Potassium bromide(aq) + Barium iodide(aq) $\to$ Potassium iodide(aq) + Barium bromide(s)

$2KB{r}_{\left(aq\right)}+{Ba{I}_2}_{\left(aq\right)}\to 2K{I}_{\left(aq\right)}+{BaB{r}_2}_{\left(s\right)}$

In this reaction, both the reactants exchange ions to form two new products. Hence, it is a double displacement reaction

(b) Zinc carbonate(s) $\to$ Zinc oxide(s) + Carbon dioxide(g)

${ZnC{O}_3}_{\left(s\right)}\to Zn{O}_{\left(s\right)}+{C{O}_2}_{\left(g\right)}$

In this reaction, a single substance yields two different products. Hence, it is a decomposition reaction.

(c) Hydrogen(g) + Chlorine(g) $\to$ Hydrogen chloride(g)

${H_2}_{\left(g\right)}+{C{l}_2}_{\left(g\right)}\to 2HC{l}_{\left(g\right)}$

In this reaction, two different reactants react with each other to form a single product. Hence, it is called a combination reaction.

(d) Magnesium(s) + Hydrochloric acid(aq) $\to$ Magnesium chloride(aq) + Hydrogen(g)

$M{g}_{\left(s\right)}+2HC{l}_{\left(aq\right)}\to {MgC{l}_2}_{\left(aq\right)}+{H_2}_{\left(g\right)}$

In this reaction, more reactive Mg is replacing less reactive H. Hence, it is displacement reaction.