In the reaction Fe₂O₃ + 2Al → Al₂O₃ + 2Fe, which element is oxidized? MCQ with Answer and Explanation

Explanation:
Atomic number = 2+8+7=17 (chlorine). Period = number of shells = 3. Valence electrons = 7 → Group 17 (10+7 for p-block). Group 18 has 8 valence electrons.

Explanation:
Hydrogenation of alkenes (addition of H₂ across double bond) is catalyzed by finely divided metals like nickel, platinum, or palladium. These adsorb H₂ and the unsaturated compound, facilitating reaction. V₂O₅ is for oxidation (Contact), MnO₂ for H₂O₂ decomposition, Fe for Haber process. Nickel is the most common industrial catalyst for hydrogenation.

Explanation:
Neutralization: Acid + Base → Salt + Water. Example: HCl + NaOH → NaCl + H₂O. It is a double displacement reaction. The pH of the resulting solution may be neutral, acidic, or basic depending on the strengths of the acid and base.