COMEDK · Chemistry · 9. Redox Reactions
The colour of \(\mathrm{CrO}_4^{2-}\) changes to \(\mathrm{Cr}_2 \mathrm{O}_7^{2-}\) is
- A yellow to orange
- B orange to yellow
- C yellow to blue
- D orange to blue
Answer & Solution
Correct Answer
(A) yellow to orange
Step-by-step Solution
Detailed explanation
The \(\mathrm{CrO}_{+}^{2-}\) (yellow) exist in acidic medium with \(\mathrm{pH}=6\) and changes to orange in basic medium as \(\mathrm{Cr}_2 \mathrm{O}_7^{2-}\) with \(\mathrm{pH}=8\).
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