Which of the following hydrocarbons is an unsaturated compound? MCQ with Answer and Explanation

Explanation:
NPK stands for Nitrogen (N), Phosphorus (P, as P₂O₅), and Potassium (K, as K₂O). These are primary macronutrients essential for plant growth. The numbers on a fertiliser bag (e.g., 10-26-26) indicate the percentage of N, P₂O₅, and K₂O.

Explanation:
Manganese dioxide (MnO₂) catalyzes the thermal decomposition of potassium chlorate: 2KClO₃ (heat, MnO₂) → 2KCl + 3O₂. Without MnO₂, decomposition requires higher temperature. MnO₂ is not consumed. Other catalysts can be used, but MnO₂ is standard in school labs. V₂O₅ is for SO₂ oxidation, Pt for various, Fe₂O₃ not typical. This is a simple preparation of oxygen.

Explanation:
Bleaching powder is chemically calcium oxychloride, with the formula CaOCl₂. It is produced by the action of chlorine gas on dry slaked lime (Ca(OH)₂). Option A is slaked lime, C is plaster of Paris, and D is washing soda. It is used for disinfecting water and bleaching textiles.