Question

5.
Statement A : Sulphur is a divalent element.
Statement B: Chlorine is a monovalent element.
Statement C: Aluminium is a trivalent element.​

Answer 1

The sign of power depends on the direction in which a light ray is deviated by the lens. The power could be positive or negative. If a lens deviates a ray towards its centre (converges), the power is positive and if it deviates the ray away from its centre (diverges), the power is negative.

Answer 2

Answer:

statement A is true

statement B is true

statement C is true