Reversibility of Chemical Reactions – Practice

Questions:

1) An equilibrium was established with a cobalt chloride solution. Predict the impact on the equilibrium and any observations that would be made if some silver nitrate was added:

2) An equilibrium was established with a cobalt chloride solution. The sample was placed in a water bath and it was observed that the solution turned from blue to pink. Explain the colour change with reference to the temperature of the water.

 

3) When sodium hydroxide is added to a solution containing Fe3+ ions, a precipitate of Iron (III) hydroxide forms. Predict the impact and any observations that would be made on an equilibrium that was established with Iron(III) nitrate and potassium thiocyanate if sodium hydroxide was added:

 

Quick Answers:

1) AgCl will precipitate, reducing the concentration of Cl. Equilibrium will shift left and the solution will become pink.

2) Equilibrium shifted left toward the exothermic side. Temperature of the system was lowered.

3) Addition of OH precipitates iron(III) hydroxide, removing Fe3+. Equilibrium will shift left and the solution will become yellow.

Worked Answers: (coming soon)