For each of the following three reactions, write a balanced equation for the reaction in part (i) and answer the question about the reaction in part (ii). Coefficients should be in terms of lowest who

Question

For each of the following three reactions, write a balanced equation for the reaction in part (i) and answer the question about the reaction in part (ii). Coefficients should be in terms of lowest whole numbers. Assume that solutions are aqueous unless otherwise indicated. Represent substances in solutions as ions if extensively ionized. Omit formulas for ions/molecules unchanged by the reaction.

Accepted Answer

a(i): 2 Mg(s) + O2(g) → 2 MgO(s). Two points are earned for reactants. One point is earned for product. One point is earned for correct balancing. a(ii): The mass increases because the mass of oxygen is added to the mass of magnesium in forming the oxide. One point is earned for correct answer with explanation. c(ii): The spectator ions are K+ and NO3-. One point is earned for correct identification of both ions, with correct formulas and charges.

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