When sodium hydroxide (NaOH) is added to the equilibrium solution, the solution will change from yellow to orange due to the formation of chromate ions, which are more favored in a basic environment. On a molecular level, the hydroxide ions (OH⁻) from NaOH react with available hydrogen ions (H⁺), thus decreasing their concentration in the solution. This shift in H⁺ concentration causes the equilibrium to shift to the left, according to Le Chatelier's principle, favoring the production of CrO₄²⁻, resulting in a predominance of yellow chromate ions and leading to a visible color change.
Chromate ions react according to the following equation, where the left side of the reaction is yellow and the right side is orange.CrO2−4 +2H ⇌ Cr2O−27 + H2OA student adds sodium hydroxide (NaOH) to the solution at equilibrium. In one to two sentences, describe a change the student will be able to see and explain the changes to the solution on the molecular level.(2 points)BoldItalicUnderlineBullet listNumbered list 0 / 10000 Word LimitShort Answer RubricCriteria PointsDescribe how the solution will change qualitatively or quantitively 1Explain:The reaction of NaOH with reactantsHow the products affect the concentration of the reactants AND products How the system shifts or restores equilibrium
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