Question

Write a conclusion statement that addresses the following questions: • Explain what the color change indicated about the changes in the concentrations of Co(H₂O)₆₂₊ and CoCl₄₂– in each trial. • Do your data support or fail to support your hypothesis (include examples)? • How do you think the investigation can be explored further?

Answer 1

The experiment's color change from pink to blue and back to pink upon the addition and subsequent dilution of HCl indicates shifts in the equilibrium.

Step-by-step explanation:

In conclusion, the color change observed during the experiment indicates a shift in the equilibrium between the Co(H₂O)₆²⁺ and CoCl₄²– ions. When HCl is added, the solution's color changes from pink to blue, showing an increase in the concentration of CoCl₄²– at the expense of Co(H₂O)₆²⁺.

This demonstrates Le Chatelier’s principle where the equilibrium shifts to counteract the added chloride ions. Our data supports the hypothesis that adding HCl will cause a shift in the equilibrium to form more CoCl₄²–, evidenced by the color change to blue.

Conversely, by adding more water, the equilibrium can be shifted back to predominantly Co(H₂O)₆²⁺, confirmed by the solution returning to pink. Exploration can be furthered by testing the effects of concentration changes, temperature, and pressure on the equilibrium.