Alpha particles are least penetrating because they: MCQ with Answer and Explanation

Explanation:
Aldehydes are organic compounds containing the formyl group, -CHO, where a carbon atom is double-bonded to an oxygen atom and single-bonded to a hydrogen atom. -OH is the hydroxyl group (alcohols), -COOH is the carboxyl group (carboxylic acids), and -CO- is the carbonyl group (ketones).

Explanation:
A positive catalyst increases reaction rate by lowering activation energy. Decreasing temperature generally slows reactions. Decreasing concentration reduces collision frequency, lowering rate. Larger pieces have less surface area, slower reaction. Other rate-increasing factors: increasing temperature, increasing pressure (for gases), using finely powdered solids, and light for photochemical reactions.

Explanation:
SO₂ (from burning coal) and NOₓ dissolve in rain to form H₂SO₄ and HNO₃. CO is toxic but does not form strong acid; CH₄ is greenhouse gas; ground-level O₃ is secondary pollutant and irritant.