IF ACIDIFIED POTASSIUM DICHROMATE(VI) (K2CR2O7) ACTS AS OXIDIZING AGENT, COLOR CHANGES FROM

• A. yellow to green
• B. orange to green ✓
• C. yellow to red
• D. orange to red

The answer to the question is: B. orange to green

When acidified potassium dichromate(VI) (K2Cr2O7) acts as an oxidizing agent, the color changes from orange to green. This is due to the reduction of the chromium(VI) ion (Cr2O72-) to chromium(III) ion (Cr3+). The orange color of the dichromate(VI) ion changes to green when it is reduced to chromium(III) ion. This reaction can be represented by the following equation:

Cr2O72- + 14H+ + 6e- → 2Cr3+ + 7H2O

This reaction involves the gain of electrons by the dichromate(VI) ion, resulting in the reduction of chromium from a +6 oxidation state to a +3 oxidation state. As a result, the color changes from orange to green.