Which of the following air pollutants is a primary cause of acid rain? MCQ with Answer and Explanation

Explanation:
Diammonium phosphate (DAP), with the formula (NH4)2HPO4, is a widely used complex fertilizer. It provides two essential macronutrients: nitrogen (from the ammonium ion) and phosphorus (from the phosphate ion). Urea and ammonium sulfate provide only nitrogen, while muriate of potash provides potassium.

Explanation:
Boiling precipitates Ca/Mg bicarbonates as carbonates, removing temporary hardness. It does not remove permanent hardness (sulfates/chlorides). It kills microbes but does not remove dissolved salts.

Explanation:
Catalysts provide an alternative pathway with lower activation energy, increasing reaction rate without being consumed. They do not affect equilibrium constant or thermodynamic parameters (ΔH, ΔS). They can be solid (heterogeneous), liquid, or gas. Enzymes are liquid-phase catalysts. A catalyst does not change the position of equilibrium, only speeds up attainment.