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The colour of K₂Cr₂O₇ changes from red orange to lemon yellow on treatment with aqueous KOH because of
- a)Reduction of Cr (VI) to Cr (III)
- b)Formation of chromium hydroxide
- c)Conversion of dichromate ion to chromate
- d)Oxidation of potassium hydroxide to potassium peroxide
Correct answer is option 'C'. Can you explain this answer?
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The colour of K₂Cr₂O₇ changes from red orange to lem...
Colour of k2cr2o7 changes from orange to lemon yellow on treatment with aqueous koh because of conversion of dichromate ion to chromate. Lemon contains citric acid.
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The colour of K₂Cr₂O₇ changes from red orange to lem...
The colour change of KCrO on treatment with aqueous KOH
The colour change of KCrO (potassium chromate) from red-orange to lemon yellow on treatment with aqueous KOH (potassium hydroxide) is due to the conversion of the dichromate ion to chromate ion.
Explanation:
1. KCrO and its colour:
KCrO is a compound that contains chromium in the +6 oxidation state. It is a red-orange colored compound.
2. Dichromate ion (Cr2O7^2-) and its colour:
The dichromate ion (Cr2O7^2-) is an orange colored ion. It contains chromium in the +6 oxidation state.
3. Chromate ion (CrO4^2-) and its colour:
The chromate ion (CrO4^2-) is a yellow colored ion. It contains chromium in the +6 oxidation state.
4. Reaction between KCrO and KOH:
When KCrO is treated with aqueous KOH, the following reaction takes place:
KCrO + KOH → K2CrO4 + H2O
In this reaction, the potassium chromate (K2CrO4) is formed along with water.
5. Conversion of dichromate ion to chromate ion:
The red-orange color of KCrO is due to the presence of the dichromate ion (Cr2O7^2-). On treatment with aqueous KOH, the dichromate ion is converted into the chromate ion (CrO4^2-). This conversion can be represented as follows:
2Cr2O7^2- + 2OH^- → Cr2O4^2- + H2O
The chromate ion is yellow in color, which explains the change in color of KCrO from red-orange to lemon yellow.
Conclusion:
The conversion of the dichromate ion (Cr2O7^2-) to the chromate ion (CrO4^2-) on treatment with aqueous KOH is responsible for the color change of KCrO from red-orange to lemon yellow.
The colour change of KCrO (potassium chromate) from red-orange to lemon yellow on treatment with aqueous KOH (potassium hydroxide) is due to the conversion of the dichromate ion to chromate ion.
Explanation:
1. KCrO and its colour:
KCrO is a compound that contains chromium in the +6 oxidation state. It is a red-orange colored compound.
2. Dichromate ion (Cr2O7^2-) and its colour:
The dichromate ion (Cr2O7^2-) is an orange colored ion. It contains chromium in the +6 oxidation state.
3. Chromate ion (CrO4^2-) and its colour:
The chromate ion (CrO4^2-) is a yellow colored ion. It contains chromium in the +6 oxidation state.
4. Reaction between KCrO and KOH:
When KCrO is treated with aqueous KOH, the following reaction takes place:
KCrO + KOH → K2CrO4 + H2O
In this reaction, the potassium chromate (K2CrO4) is formed along with water.
5. Conversion of dichromate ion to chromate ion:
The red-orange color of KCrO is due to the presence of the dichromate ion (Cr2O7^2-). On treatment with aqueous KOH, the dichromate ion is converted into the chromate ion (CrO4^2-). This conversion can be represented as follows:
2Cr2O7^2- + 2OH^- → Cr2O4^2- + H2O
The chromate ion is yellow in color, which explains the change in color of KCrO from red-orange to lemon yellow.
Conclusion:
The conversion of the dichromate ion (Cr2O7^2-) to the chromate ion (CrO4^2-) on treatment with aqueous KOH is responsible for the color change of KCrO from red-orange to lemon yellow.
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The colour of K₂Cr₂O₇ changes from red orange to lemon yellow on treatment with aqueous KOH because ofa)Reduction of Cr (VI) to Cr (III)b)Formation of chromium hydroxidec)Conversion of dichromate ion to chromated)Oxidation of potassium hydroxide to potassium peroxideCorrect answer is option 'C'. Can you explain this answer?
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The colour of K₂Cr₂O₇ changes from red orange to lemon yellow on treatment with aqueous KOH because ofa)Reduction of Cr (VI) to Cr (III)b)Formation of chromium hydroxidec)Conversion of dichromate ion to chromated)Oxidation of potassium hydroxide to potassium peroxideCorrect answer is option 'C'. Can you explain this answer? for NEET 2024 is part of NEET preparation. The Question and answers have been prepared according to the NEET exam syllabus. Information about The colour of K₂Cr₂O₇ changes from red orange to lemon yellow on treatment with aqueous KOH because ofa)Reduction of Cr (VI) to Cr (III)b)Formation of chromium hydroxidec)Conversion of dichromate ion to chromated)Oxidation of potassium hydroxide to potassium peroxideCorrect answer is option 'C'. Can you explain this answer? covers all topics & solutions for NEET 2024 Exam. Find important definitions, questions, meanings, examples, exercises and tests below for The colour of K₂Cr₂O₇ changes from red orange to lemon yellow on treatment with aqueous KOH because ofa)Reduction of Cr (VI) to Cr (III)b)Formation of chromium hydroxidec)Conversion of dichromate ion to chromated)Oxidation of potassium hydroxide to potassium peroxideCorrect answer is option 'C'. Can you explain this answer?.
The colour of K₂Cr₂O₇ changes from red orange to lemon yellow on treatment with aqueous KOH because ofa)Reduction of Cr (VI) to Cr (III)b)Formation of chromium hydroxidec)Conversion of dichromate ion to chromated)Oxidation of potassium hydroxide to potassium peroxideCorrect answer is option 'C'. Can you explain this answer? for NEET 2024 is part of NEET preparation. The Question and answers have been prepared according to the NEET exam syllabus. Information about The colour of K₂Cr₂O₇ changes from red orange to lemon yellow on treatment with aqueous KOH because ofa)Reduction of Cr (VI) to Cr (III)b)Formation of chromium hydroxidec)Conversion of dichromate ion to chromated)Oxidation of potassium hydroxide to potassium peroxideCorrect answer is option 'C'. Can you explain this answer? covers all topics & solutions for NEET 2024 Exam. Find important definitions, questions, meanings, examples, exercises and tests below for The colour of K₂Cr₂O₇ changes from red orange to lemon yellow on treatment with aqueous KOH because ofa)Reduction of Cr (VI) to Cr (III)b)Formation of chromium hydroxidec)Conversion of dichromate ion to chromated)Oxidation of potassium hydroxide to potassium peroxideCorrect answer is option 'C'. Can you explain this answer?.
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