Which of the following is an example of a homogeneous catalyst? MCQ with Answer and Explanation

Explanation:
Copper pyrites (CuFeS₂) is a sulfide ore, concentrated by froth flotation using pine oil and water. Then roasting, smelting, and refining.

Explanation:
Detergents (e.g., sulfonates) do not precipitate with Ca²⁺/Mg²⁺, so they lather well in hard water. Soaps form insoluble scum. This is a major advantage.

Explanation:
Organic fertilizers (compost, manure, bone meal) add humus, improving soil structure, water retention, and aeration. They support beneficial microorganisms that slowly decompose organic matter, releasing nutrients gradually. Unlike synthetic fertilizers, they do not cause sudden nutrient spikes or soil acidification. Biofertilizers like Rhizobium fix nitrogen. Organic farming emphasizes sustainability and reduced chemical inputs.