Question

Reema took 5 ml of lead nitrate solution in a beaker and added approximately 4 ml of potassium iodide solution to it. what would she observe?

Answer 1

Reaction of Lead nitrate and Potassium iodide:-

• Precipitation reaction is a type of reaction where two ionic salts are reacted with each other.
• This results in the formation of an insoluble salt, that is the salt formed is not soluble in water.
• The reaction between Lead nitrate$\left({\mathrm{PbNO}}_3\right)$ and Potassium iodide$\left(\mathrm{KI}\right)$results in the formation of Lead iodide$\left({\mathrm{PbI}}_2\right)$ and Potassium nitrate$\left({\mathrm{KNO}}_3\right)$.
• This Lead iodide formed is a yellow precipitate.
• The complete reaction is:

$\underset{\mathrm{Lead}\mathrm{nitrate}}{\mathrm{Pb}{\left({\mathrm{NO}}_3\right)}_2\left(\mathrm{aq}\right)}+\underset{\mathrm{Potassum}\mathrm{iodide}}{2\mathrm{KI}\left(\mathrm{aq}\right)}\to \underset{\mathrm{Lead}\mathrm{iodide}}{{\mathrm{PbI}}_2\left(\mathrm{s}\right)(\downarrow )\left(\mathrm{yellow}\right)}+\underset{\mathrm{Potassium}\mathrm{nitrate}}{2{\mathrm{KNO}}_3\left(\mathrm{aq}\right)}$

• Thus this reaction is an example of a precipitation reaction.

Therefore, Reema observes that a yellow ppt of Lead iodide is being formed due to the reaction of Lead nitrate and Potassium iodide.