Question

24. Identify a source of error for the experimental design of the cobalt(II)chloride system

In the experiment, there were three test tubes.
All of them contained cobalt(II)chloride.
Test tube 1 was the constant, therefore, did not change throughout the experiment.
Test tube 2, water was added to see how that affects equilibrium change (the color changed from blue to pink)
Then later, the same test tube was placed in a warm water bath (changing temperature) and the color changed from pink to blue and equilibrium shifted.
Test tube 3, added silver nitrate to decrease the concentration of the chloride ions (a precipitate formed) and the color changed from blue to pink.