Question

Which among the following compounds in crystalline form is used for making Nicol's prism?

विकल्प

• CaSO₄

• Na₂AIF₆

• CaCO₃

• Al₂O₃

Answer 1

CaCO₃ 

Explanation:

Calcite crystal (I.e. calcium carbonate in crystalline form) is generally known as calc-spar and is used to produce and analyse plane polarised light.