Question

The molecular formula of Glauber’s salt is:
(a)-$MgS{{O}_{4}}.7{{H}_{2}}O$
(b)-$CuS{{O}_{4}}.5{{H}_{2}}O$
(c)-$FeS{{O}_{4}}.7{{H}_{2}}O$
(d)-$N{{a}_{2}}S{{O}_{4}}.10{{H}_{2}}O$

Answer 1

Hint: This is the salt of the element which belongs to s-block, alkali metals group. That element is the seventh most abundant element by weight in the earth's crust. It is also known as mirabilite.

Complete answer:
Glauber's salt is the salt of the sodium element. The decahydrate form of sodium sulfate is known as Glauber’s salt.
Since it is the hydrated form of sodium sulfate its formula is:$N{{a}_{2}}S{{O}_{4}}.10{{H}_{2}}O$
It is a vitreous mineral.
It is a white or colorless crystal which on evaporation leaves sodium sulfate.
They naturally occur in saline playa lakes and around the saline springs.
They undergo quick dehydration because they are very unstable in dry air.
When dehydrated in such conditions it converts into a white powder which has the formula .
It is also called thenardite.

Properties of Glauber's salt:
Its molecular mass is 322.2 g/mol.
It has a monoclinic crystal structure.
The density of the salt is 1.464 grams per cubic centimeter under normal conditions.
Since it is the salt of sodium it is not radioactive and does not give the property of fluorescence.
Its melting point is 32.38$^{\circ }C$

Uses:
Glauber’s salt is used in the medical field as a laxative.
Sometimes the body gets overdosed with paracetamol so, to remove it Glauber's salt is used.
It can be used for making the mats of laptops and computers.
So, the correct answer is “Option D”.

Note: Since it is the salt of the s-block group don't get confused between $N{{a}_{2}}S{{O}_{4}}.10{{H}_{2}}O$ and $MgS{{O}_{4}}.7{{H}_{2}}O$. Because $MgS{{O}_{4}}.7{{H}_{2}}O$ is also an s-block element salt. Sometimes in the options $N{{a}_{2}}S{{O}_{4}}.10{{H}_{2}}O$ and $N{{a}_{2}}S{{O}_{4}}$ should be given then the correct answer is because Glauber's salt is hydrated form.