The questions below refer to the following system:
Co(H 2 O) 6 2+ + 4 Cl - CoCl 4 2 - + 6H 2 O
(pink)
(blue)
When cobalt(II)chloride is added to pure water,the Co 2+ ions hydrate.The hydrated form then reacts with the Cl - ions to set up the equilibrium shown here.
-Which statement below describes the change that the system will undergo if hydrochloric acid is added?

Question

The questions below refer to the following system:
Co(H 2 O) 6 2+ + 4 Cl -  CoCl 4 2 - + 6H 2 O
(pink)
(blue)
When cobalt(II)chloride is added to pure water,the Co 2+ ions hydrate.The hydrated form then reacts with the Cl - ions to set up the equilibrium shown here.
-Which statement below describes the change that the system will undergo if hydrochloric acid is added?

Quizplus · Accepted Answer

Adding hydrochloric acid to a system in equilibrium will increase the concentration of hydrogen ions (H+), which will shift the equilibrium towards the side that consumes these ions. In the context of an acid-base indicator like bromothymol blue, which turns yellow in acidic conditions and blue in basic conditions, adding an acid would shift the equilibrium to produce more H+ ions, making the solution more acidic and thus more yellow (not blue). However, without specific details on the reaction or the indicator used (assuming a different scenario might involve a pink color change for a specific indicator), the general principle of Le Chatelier's principle applies, indicating a shift in equilibrium due to the added acid. Since the question does not specify the exact chemical system or indicator, the correct answer involves recognizing that the equilibrium will shift (either to the right or left depending on the specific reaction) due to the addition of hydrochloric acid, but without more details, both shifting of equilibrium and a potential color change (if considering acid-base indicators in a general sense) could be considered correct. However, the explanation provided focuses on the principle of equilibrium shift due to added reactants.

The Questions Below Refer to the Following System