Chlorine is added to drinking water to: MCQ with Answer and Explanation

Explanation:
Flooded rice paddies promote anaerobic decomposition of organic matter, producing methane (CH₄). It is a potent greenhouse gas. Livestock also emit methane.

Explanation:
Vitamin C is chemically known as ascorbic acid (C6H8O6). It is a vital nutrient involved in the repair of tissue and the enzymatic production of certain neurotransmitters. Deficiency leads to scurvy. Retinol is Vitamin A, Calciferol is Vitamin D, and Tocopherol is Vitamin E.

Explanation:
Portland cement is made by heating a mixture of limestone (CaCO₃) and clay (containing SiO₂, Al₂O₃, Fe₂O₃) in a rotary kiln at high temperature, forming clinker, which is then ground with a small amount of gypsum to control setting. Gypsum alone is added as a retarder, not raw material. The major compounds formed are tricalcium silicate, dicalcium silicate, tricalcium aluminate, and tetracalcium aluminoferrite.