Question

The Salt Story

From: The New Indian Express 9 March 2021

The salt pans in Marakkanam, a port town about 120 km from Chennai are the third largest producer of salt in Tamil Nadu. Separation of salt from water is a laborious process and the salt obtained is used as raw materials for manufacture of various sodium compounds.

One such compound is Sodium hydrogen carbonate, used in baking, as an antacid and in soda acid fire extinguishers.

The table shows the mass of various compounds obtained when 1litre of sea water is evaporated.

COMPOUND	FORMULA	MASS OF SOLID PRESENT /g
Sodium Chloride	NaCl	28.0
Magnesium Chloride	MgCl2	8.0
Magnesium Sulphate	MgSO4	6.0
Calcium Sulphate	CaSO4	2.0
Calcium Carbonate	CaCO3	1.0
TOTAL AMOUNT OF SALT OBTAINED		45.0

How many grams of Magnesium Sulphate are present in 135g of solid left by evaporation of sea water?

Options

• 6g

• 12g

• 18g

• 24g

Answer 1

18g