What will happen if hydrochloric acid is added to the following equilibrium system?
H+(aq) + 2 CrO42-(aq) ⇔ Cr2O72-(aq) + OH-(aq)
yellow orange
If hydrochloric acid (HCl) is added to the equilibrium system, it will increase the concentration of H+ ions in the solution. According to Le Chatelier's principle, the system will shift to the left in order to counteract the increase in H+ ions.
As a result, the concentration of H+ ions will increase, causing a decrease in the concentration of CrO42- ions. This will shift the equilibrium towards the reactant side, leading to a decrease in the intensity of the yellow color of the solution.
However, the concentration of OH- ions will also decrease, which will cause the equilibrium to shift towards the product side to increase the concentration of OH- ions. This will result in an increase in the intensity of the orange color of the solution.
Overall, the addition of hydrochloric acid will cause the system to shift to the left, resulting in a decrease in the intensity of the yellow color and an increase in the intensity of the orange color.
are you sure?
I apologize for the incorrect response. I made a mistake in my explanation.
If hydrochloric acid (HCl) is added to the equilibrium system, it will increase the concentration of H+ ions in the solution. According to Le Chatelier's principle, the system will shift to the right to counteract the increase in H+ ions.
As a result, the concentration of H+ ions will increase, causing a decrease in the concentration of OH- ions. This will shift the equilibrium towards the reactant side, leading to an increase in the concentration of CrO42- ions and a decrease in the concentration of Cr2O72- ions.
The color change in this equilibrium is due to the change in chromium oxidation states. The reactant, CrO42-, has a yellow color, while the product, Cr2O72-, has an orange color. Therefore, as the equilibrium shifts to the right, more CrO42- will be converted into Cr2O72-, causing the solution to become more orange.
So, to correct my previous response, the addition of hydrochloric acid will cause the system to shift to the right, resulting in the solution becoming more orange.
When hydrochloric acid (HCl) is added to the equilibrium system H+(aq) + 2 CrO42-(aq) ⇔ Cr2O72-(aq) + OH-(aq), it will react with the OH- ions on the right side of the equation. The reaction between HCl and OH- ions is a neutralization reaction that forms water (H2O) and chloride ions (Cl-).
HCl(aq) + OH-(aq) → H2O(l) + Cl-(aq)
The addition of HCl to the equilibrium will remove the OH- ions from the right side of the reaction, prompting the equilibrium to shift towards the right to replace the OH- ions that were consumed. As a result, the concentration of Cr2O72-(aq) and the orange color will increase.
This can be explained by Le Chatelier's principle, which states that when a system at equilibrium is subjected to a change, it will tend to counteract that change and shift the equilibrium position. In this case, the addition of HCl causes a decrease in OH- concentration, so the system will shift to the side where OH- ions are formed, which is the right side.
Therefore, when HCl is added, the equilibrium will shift to the right, resulting in an increase in the concentration of Cr2O72-(aq) and a deepening of the orange color in the solution.