Which of the following is the correct balanced equation for the reaction between aluminum and permanganate ions in an aqueous solution?

A 6.53-g sample of a mixture of magnesium carbonate and calcium carbonate is treated with excess hydrochloric acid. The resulting reaction produces 1.72 L of carbon dioxide gas at 28 °C and 99.06 kPa pressure. (a) Write balanced chemical equations for the reactions that occur between hydrochloric acid and each component of the mixture.

Hydrazine (N₂H₄) and dinitrogen tetroxide (N₂O₄) form a self-igniting mixture that has been used as a rocket propellant. The reaction products are N₂ and H₂O. (a) Write a balanced chemical equation for this reaction.

(a) Write a chemical equation that describes the attack of acid rain on limestone, CaCO₃.