Question

Distinguish between the following pairs of compound using the test given within brackets:
Iron (II) sulphate ions and iron (III) sulphate (ammonium hydroxide)

Answer 1

Hint: When iron(II) sulphate is reacted with the ammonium hydroxide then it gives green colour precipitates and on the reaction with iron(III) sulphate it gives orange precipitates due to the formation of different hydrates in it.

Complete step by step solution: When iron(II) sulphate is reacted with the ammonium hydroxide then it gives green colour precipitates and on the reaction with iron(III) sulphate it gives orange precipitates due to the formation of two and three hydroxide ions respectively in the reaction which is clearly visible through the difference in the colour.
When talking about iron(II) sulphate which also known as ferrous sulphate makes or we can say that it contributes to the range of salts and further exists in the heptahydrate form . An interesting fact that this test is used to check the deficiency of iron and also for industrial applications.
Then talking about the iron(III) sulphate which is also called ferric sulphate it’s colour is yellow and it is further soluble in water. It also forms a variety of hydrates. It is further used for dyeing and for industrial use also it is used.
Further we can say that due to the formation of different types of hydrates we can say that it gives different colour precipitate when ammonium hydroxide is reacted with both of them.

Note:

Properties of correspondingsolution	Iron(II) sulphate	Iron(III) sulphate
Oxidation state of iron	+2	+3
Original color of the salt	Light bluish green	Yellow
Color of precipitate observed	Pale green	Orange(reddish brown)
Uses	To test deficiency of iron	For dyeing