Question

**OR** (B) (a) Study the experimental setup shown in the diagram and write chemical equation for the same. Name and define the type of reaction. Mention the colour of the products formed. (b) What type of reaction takes place when aqueous solution of lead (II) nitrate and potassium iodide are mixed together? Write chemical equation also.

Accepted Answer

(a) Equation: $2	ext{Pb(NO}_3)_2(s) \xrightarrow{\Delta} 2	ext{PbO}(s) + 4	ext{NO}_2(g) + 	ext{O}_2(g)$ Type of reaction: **Thermal Decomposition** (a reaction where a single substance breaks down into two or more simpler substances upon heating). Product colours: Lead oxide ($	ext{PbO}$) is **yellow**, Nitrogen dioxide ($	ext{NO}_2$) is a **brown gas**. (b) Type of reaction: **Double Displacement / Precipitation Reaction**. Equation: $	ext{Pb(NO}_3)_2(aq) + 2	ext{KI}(aq) ightarrow 	ext{PbI}_2(s)\downarrow + 2	ext{KNO}_3(aq)$ (Yellow precipitate of $	ext{PbI}_2$).

Thermal decomposition of lead nitrate and precipitation reaction

Explanation

Practise this under board exam conditions