Question

Difference between coprecipitation and post precipitation.

Answer 1

Hint: The chemical which is going to be formed during the chemical reaction of different reactants is not going to be soluble in the solvent where the chemical reaction is going to occur, then the product formed is going to settle as a precipitate.

Complete answer:
- In the question it is asked to write the difference between coprecipitation and post precipitation.
- The differences between coprecipitation and post precipitation is as follows.

S. NO	Coprecipitation	Post precipitation
1.	Generally in this process the soluble impurities are going to be removed by making them precipitate.	The precipitate which is going to form on the surface of the other precipitate is called post precipitation.
2.	The desired compound is going to be precipitated in this process.	In this process the first desired compound is going to be precipitated and later the undesired compound is going to be precipitated on the surface of the desired compound.
3.	In this process the degree of contamination is too high.	In this process the degree of contamination is low.
4.	Example for this co precipitation is precipitation of silver ions with other ions during the precipitation of silver chloride.	Formation of the precipitate of calcium oxalate on the surface of the magnesium oxalate

Note:
The phenomenon of coprecipitation and post precipitation are going to occur in the process of gravimetric analysis. Both the precipitation are going to occur in the presence of the solvent or by adding the solvent to the chemicals.