Which metal oxide is amphoteric? MCQ with Answer and Explanation

Explanation:
CO₂ is the primary anthropogenic greenhouse gas from fossil fuel combustion. N₂, O₂ not IR active. Ammonia is not a major GHG. Methane, N₂O also contribute.

Explanation:
James Chadwick discovered the neutron in 1932. He bombarded beryllium with alpha particles and observed a highly penetrating, neutral radiation, which he identified as neutrons. This discovery explained isotopes and completed the basic picture of the atom's subatomic particles.

Explanation:
Across a period from left to right, atomic radius decreases due to increasing effective nuclear charge. Therefore, the correct order for period 3 elements is Na > Mg > Al > Si. Down a group, radius increases, so F < Cl < Br < I. Options A, C, and D have incorrect trends.