Question

Write the equation for the reaction, if any, that occurs when each of the following experiments is performed under standard conditions. (a) Sulfur is added to mercury. (b) Manganese dioxide in acidic solution is added to liquid mercury. (c) Aluminum metal is added to a solution of potassium ions.

Short answer

Answer: Experiment (b) involved a chemical reaction, and the balanced chemical equation for that reaction is: 2Hg (l) + MnO2 (s) + 4H^+ (aq) -> 2Hg^2+ (aq) + Mn^2+ (aq) + 2H2O (l).

Step-by-step solution

Identify reactive species

In this experiment, we have sulfur (S) and mercury (Hg).

Determine if a reaction will occur

Sulfur and mercury can chemically react to form mercury sulfide (HgS) under certain conditions. However, under standard conditions, sulfur does not react with mercury. Therefore, there is no reaction in this case. ##Experiment (b): Manganese dioxide in acidic solution is added to liquid mercury##

Identify reactive species

In this experiment, we have manganese dioxide (MnO2) in acidic solution and liquid mercury (Hg).

Determine if a reaction will occur

Manganese dioxide in acidic solution can act as an oxidizing agent in a redox reaction. Liquid mercury can be oxidized to form mercuric ions (Hg^2+). Therefore, a reaction will occur between MnO2 and Hg in an acidic solution.

Write the balanced chemical equation

For this reaction, we have: 2Hg + MnO2 + 4H^+ -> 2Hg^2+ + Mn^2+ + 2H2O The balanced chemical equation for the reaction in an acidic solution is: 2Hg (l) + MnO2 (s) + 4H^+ (aq) -> 2Hg^2+ (aq) + Mn^2+ (aq) + 2H2O (l) ##Experiment (c): Aluminum metal is added to a solution of potassium ions##

Identify reactive species

In this experiment, we have aluminum metal (Al) and a solution containing potassium ions (K^+).

Determine if a reaction will occur

Aluminum is more reactive than potassium, so it can replace potassium in a solution. However, since potassium ions (K^+) are already in their most stable oxidation state (i.e., they have already lost an electron), no reaction will occur in this case. Therefore, there is no reaction in experiment (a) and (c), while experiment (b) involves a redox reaction, as shown by the balanced chemical equation.