Which of the following is a negative catalyst (inhibitor)?
A. Phosphoric acid in decomposition of H₂O₂
B. Fe in Haber process
C. MnO₂ in decomposition of H₂O₂
D. Pt in oxidation of SO₂
Answer: Option A
Solution (By JKExamLibrary)
A negative catalyst (inhibitor) slows down a reaction. Phosphoric acid (or acetamide) retards the decomposition of H₂O₂ by stabilizing it. MnO₂ is a positive catalyst for H₂O₂ decomposition, speeding it up. Platinum catalyzes SO₂ oxidation in contact process. Iron (Fe) catalyzes ammonia synthesis in Haber process. Negative catalysts are often used to prevent undesirable reactions, e.g., antioxidants in food preservation.
Explanation:
Bauxite (Al₂O₃·2H₂O) is the primary ore of aluminum. Haematite (Fe₂O₃) is an ore of iron. Cinnabar (HgS) is an ore of mercury, and Galena (PbS) is an ore of lead. Bauxite is purified to alumina before being electrolyzed to extract pure aluminum metal.
Explanation:
Mg goes from 0 to +2 oxidation state, losing electrons – oxidized. Oxygen is reduced (0 to -2). This is a combustion/combination redox reaction.
Explanation:
In a double displacement reaction, ions of two compounds exchange places to form two new compounds. Here, Ba²⁺ and Na⁺ exchange their anions (Cl⁻ and SO₄²⁻) to form BaSO₄ (a white precipitate) and NaCl. This is also a precipitation reaction due to the formation of insoluble barium sulfate.
No comments yet. Be the first to start the discussion!