Which of the following metals is the best conductor of heat? MCQ with Answer and Explanation

Explanation:
Cement undergoes hydration reactions: water reacts with cement compounds (C₃S, C₂S, C₃A) to form complex hydrated silicates and aluminates (e.g., C-S-H gel) along with Ca(OH)₂. This process causes setting and hardening, forming a rigid, rock-like mass. It is exothermic. Gypsum controls initial setting. Proper curing is necessary for strength development.

Explanation:
Gamma rays are high-frequency electromagnetic waves emitted from the nucleus. They have very high penetration power and are used in cancer therapy.

Explanation:
Hydrochloric acid (HCl) was historically called muriatic acid or spirits of salt, produced from salt (NaCl) and sulfuric acid. Oil of vitriol is H₂SO₄. Aqua regia is a mixture of 3 parts HCl and 1 part HNO₃. Carbolic acid is phenol. HCl is present in gastric juice and used in metal cleaning and chemical synthesis.