The phenomenon of global warming is primarily linked to an increase in: MCQ with Answer and Explanation

Explanation:
Manganese dioxide (MnO₂) catalyzes H₂O₂ decomposition: 2H₂O₂ → 2H₂O + O₂. Finely divided MnO₂ is added. Other catalysts include catalase enzyme.

Explanation:
Natural gas is primarily methane (CH₄), typically 70-90%, along with small amounts of ethane, propane, butane, and other hydrocarbons. It is a fossil fuel formed from the remains of ancient marine organisms. CNG (compressed natural gas) is methane stored at high pressure. LPG (liquefied petroleum gas) mainly contains propane and butane. Methane has the highest calorific value among the given options per unit mass.

Explanation:
Filtration uses filter paper or other porous medium that allows liquid to pass but retains solid particles. Distillation separates liquids by boiling points; sublimation separates sublimable solids; chromatography separates based on differential adsorption. Example: separating sand from water.