Acid rain is primarily caused by the emission of: MCQ with Answer and Explanation

Explanation:
Evaporation increases with an increase in surface area, temperature, and wind speed, and decreases with an increase in humidity. A larger surface area allows more liquid molecules to be exposed to the air, enabling them to escape into the vapor phase more quickly, thus increasing the rate of evaporation.

Explanation:
The unwanted earthy or sandy impurities present in an ore are called gangue (or matrix). Flux is added during smelting to react with these impurities, and the resulting fused mass is called slag, which is lighter and floats on top of the molten metal for easy removal.

Explanation:
Immiscible liquids (e.g., oil and water) form separate layers. A separating funnel is used to draw off the denser liquid from the bottom. Distillation methods are used for miscible liquids. Centrifugation separates solids from liquids or liquids of different densities in a mixture but not for two immiscible liquids efficiently in a lab; a separating funnel is simpler.