Soap scum is formed due to the reaction of soap with:
A. Chloride ions
B. Sodium ions
C. Calcium and magnesium ions
D. Potassium ions
Answer: Option C
Solution (By JKSSB Mock Tests)
Soap (sodium carboxylate) reacts with Ca²⁺/Mg²⁺ to form insoluble calcium or magnesium carboxylate (scum). This precipitates and reduces cleaning efficiency. Sodium and potassium salts are soluble. This is why detergents, which form soluble Ca/Mg salts, are used. Scum is visible in hard water areas.
Explanation:
Polycarbonate is a tough, transparent thermoplastic used in bulletproof glass, CDs, and lenses. Polyethylene is for bags; PVC for pipes; Bakelite is thermoset.
Explanation:
Urea is synthesized by reacting ammonia and carbon dioxide under high pressure and temperature: 2NH₃ + CO₂ → NH₂COONH₄ (ammonium carbamate) → (NH₂)₂CO + H₂O. This is the Bosch-Meiser urea process. It is the most concentrated solid nitrogenous fertilizer. Urea is also used in animal feed, plastics, and pharmaceuticals.
Explanation:
At cathode (negative electrode), H⁺ ions are reduced: 2H⁺ + 2e⁻ → H₂(g). At anode (positive), water is oxidized: 2H₂O → O₂ + 4H⁺ + 4e⁻. Overall: 2H₂O → 2H₂ + O₂. The volume of H₂ collected is double that of O₂. Acidified water (with H₂SO₄) enhances conductivity. Platinum electrodes are used.
No comments yet. Be the first to start the discussion!