Nitric acid reacts with copper to produce: MCQ with Answer and Explanation

Explanation:
AgNO₃ + NaCl → AgCl↓ + NaNO₃ is a double displacement (precipitation) reaction where ions exchange partners. Ag⁺ pairs with Cl⁻ to form a white precipitate of AgCl, and Na⁺ remains with NO₃⁻. Option A is combination, B is single displacement, D is decomposition. Double displacement generally forms a precipitate, gas, or water. Neutralization is also a double displacement: HCl + NaOH → NaCl + H₂O.

Explanation:
PVC is a good electrical insulator, resistant to chemicals and moisture, used for pipes, cable sheathing. Bakelite for switches; polystyrene for packaging.

Explanation:
Use Charles' law: V₁/T₁ = V₂/T₂. T in Kelvin: T₁ = 27+273 = 300 K, T₂ = 327+273 = 600 K. V₂/V₁ = T₂/T₁ = 600/300 = 2. Volume doubles. The ratio is 2:1. Note that 27 to 327 is a 300°C increase, but absolute temperature doubles.