Question

What is the formula of white vitriol?
(A) $ZnS{{O}_ {4}}. {{H}_ {2}} O$
(B) $ZnS{{O}_{4}}.4{{H}_ {2}} O$
(C) $ZnS{{O}_{4}}.6{{H}_ {2}} O$
(D) $ZnS{{O}_{4}}.7{{H}_ {2}} O$

Answer 1

Hint: To solve this question, recall the properties of zinc sulphate, as it is water soluble, clear, crystalline compound prepared by heating sulphide ore in air and recrystallizing the sulphate.

Complete answer:
We have been provided white vitriol,
We need to write the formula of this compound,
So, for that:
We know that white vitriol is basically zinc sulphate,
So, it is formed or prepared by reacting zinc with aqueous sulphuric acid,
\[Zn+{{H}_ {2}} S{{O}_ {4}} \to ZnS{{O}_ {4}} +{{H}_ {2}} \]
And we know that zinc sulphate is water soluble,
Due to which it forms, zinc sulphate heptahydrate which is the mineral goslarite,
And this zinc sulphate heptahydrate was historically known as white vitriol,
Also, white vitriol has certain applications too which are:
It is used in making lithopone, as a preservative for skin and leather, and in medicine as an astringent ad emetic and also as a mordant in dyeing.
Its main application is that it is used as a coagulant in the production of rayon,
Zinc sulphate heptahydrate also has applications related to agricultural practices as it is used in fertilizers, and agricultural sprays. It is also used to supply zinc in animal feeds
Now, the formula for white vitriol that is also known as zinc sulphate heptahydrate is: $ZnS{{O}_ {4}}. {{H}_ {2}} O$,
So, we can say that the formula of white vitriol is $ZnS{{O}_ {4}}. {{H}_ {2}} O$,

So, we can say that the correct option is (D).

Note:
Zinc sulphate has some limitations too: as exposure to zinc sulphate can cause headache, dizziness, nausea and vomiting. But there are no exposure limits still it may pose a health risk.