Predict the color change when a base is added into potassium dichromate solution
Correct answer: B. Orange to yellow
- A. Yellow to blue
- B. Orange to yellow
- C. Yellow to orange
- D. Green to yellow
Explanation
Potassium dichromate is a powerful oxidizing agent, and its color changes depending on its oxidation state. In an acidic solution, it exists as dichromate ion Cr2O72- which is orange in color. However, when a base is added to the solution, the dichromate ion reacts to form the chromate ion CrO42- which is yellow in color.
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About Redox Reactions
Redox reactions involve oxidation and reduction occurring together, with electrons transferred between species or oxidation numbers changing. The topic covers assigning oxidation states, identifying oxidizing and reducing agents, balancing redox equations by oxidation number or half-reaction methods, and connecting chemical changes with galvanic and electrolytic cells.
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