What is the percentage of Calcium in Calcium Carbonate?

Question

Question

This question was previously asked in

WBPSC Miscellaneous Preliminary Exam 2019 Official Paper (Held On: 08 Mar, 2020)

Answer 1

The correct answer is 40.

Key Points

Calcium Carbonate (CaCO₃) is a chemical compound commonly found in rocks, and it is the main component of shells of marine organisms, snails, and eggs.
Calcium Carbonate consists of 40% calcium by atomic weight.
The molecular weight of Calcium Carbonate is 100 g/mol, with calcium contributing 40 g/mol to this weight.
To find the percentage of calcium in Calcium Carbonate, the formula is (Atomic weight of Calcium / Molecular weight of CaCO₃) * 100.
Using the formula: (40/100) * 100 = 40%. Therefore, the percentage of calcium in Calcium Carbonate is 40%.

Additional Information

Calcium Carbonate is used in various applications, including as a dietary supplement, in the construction industry, and as a raw material in the production of lime and cement.
It is also used in the purification of iron from iron ore in a blast furnace.
In the medical field, Calcium Carbonate is used as an antacid to relieve heartburn, acid indigestion, and upset stomach.