Practicing Success
Which of the following is an example of a double salt? |
Cuprammonium sulphate Mohr’s salt Potassium ferricyanide Cobalthexammine chloride |
Mohr’s salt |
The correct answer is: (b) Mohr's salt Mohr's salt is an example of a double salt. It is also known as ferrous ammonium sulfate \([(NH_4)_2Fe(SO_4)_2·6H_2O]\). Double salts are crystalline compounds that result from the combination of two simple salts in stoichiometric proportions. In the case of Mohr's salt, it is formed by the combination of ferrous sulfate \((FeSO_4)\) and ammonium sulfate \(((NH_4)_2SO_4)\) in a 1:1 molar ratio. Let's look at the other options: (a) Cuprammonium sulphate - This is not a double salt. It is formed through the dissolution of copper(II) oxide or copper(II) hydroxide in excess ammonia to form a complex ion \([Cu(NH_3)_4]^{2+}\) in the solution. |