Question

(a) What is a salt? Give the names and the formula of any two salts. Also name the acids and bases from which these salts may be obtained.
(b) What is meant by a family of salts? Explain with examples.
(c) What is meant by hydrated and anhydrous salts? Explain with examples.
(d) Write the names formulae and colour of any two hydrated salts.
(e) What will be the colour of litmus in an aqueous solution of ammonium chloride salt?

Answer 1

Hint: The product formed from the reaction of an acid and a base is commonly known as salt. Similar types of salt form a family of salts. The salts with water of crystallization are known as hydrous salts and rest of them are anhydrous salts.

Complete step by step answer:
Chemical compound: A chemical substance composed of one or more identical and different elements or molecules is known as a chemical compound.
(a)
Salt: In the chemical reaction of an acid with a metal, when the hydrogen atom is replaced by the metal then the resultant product is known as salt.
Examples: Sodium chloride ( $ NaCl $ ) [Formed from the sodium metal and hydrochloric acid]
Magnesium chloride ( $ MgC{l_2} $ ) [Formed from the magnesium metal and hydrochloric acid]
(b)
The number of salts having the same cation or we can say the same positive ion present in the chemical formula contributes to form the family of salts.
Example: All the sodium salts belong from the same family of salts such as sodium chloride and sodium sulphate.
(c)
The salts containing water molecules in their chemical formula are known as hydrated salts while the salt which doesn’t contain water of crystallization are known as anhydrous salts.
Example: $ {\text{CuS}}{{\text{O}}_{\text{4}}}{\text{.5}}{{\text{H}}_{\text{2}}}{\text{O}} $ [Hydrates salt], $ {\text{CuS}}{{\text{O}}_{\text{4}}} $ [anhydrous salt]
(d)
The two common names of hydrated salts used in chemistry are iron sulphate heptahydrate and copper sulphate pentahydrate.
The chemical formulas are;
Iron sulphate heptahydrate: $ {\text{FeS}}{{\text{O}}_{\text{4}}}{\text{.7}}{{\text{H}}_{\text{2}}}{\text{O}} $
Its colour is Green.
Copper sulphate pentahydrate: $ {\text{CuS}}{{\text{O}}_{\text{4}}}{\text{.5}}{{\text{H}}_{\text{2}}}{\text{O}} $
Its colour is Blue.
(e)
As we all know that ammonium chloride is made up of strong acid and weak acid, so overall it is acidic in nature and has the capacity to convert blue litmus into red. Therefore the colour of litmus in an aqueous solution of ammonium chloride salt is red.

Note: The colour of salts correspondent to metal are as follows:

Metal in salt	Colour
Calcium	Orange
Sodium	Yellow
Copper	Blue
Iron	Green