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Many copper (I) compounds are unstable in aqueous solution and undergo disproportionation as 2Cu+ → Cu + Cu2+ . This is due to
- a)free energy change of reaction is positive
- b)free energy of reaction is negative
- c)second ionisation energy of Cu is higher than first ionisation energy
- d)hydration energy of Cu+ is less than Cu2+
Correct answer is option 'B'. Can you explain this answer?
Most Upvoted Answer
Many copper (I) compounds are unstable in aqueous solution and undergo...
Cu+ is unstable in aqueous solution than Cu2+ because although 2nd I.E. of copper is large but hydration enthalpy for Cu2+ is much more negative than that for Cu+ and hence, it is more than compensates for the 2nd I.E. of copper. Therefore, many Cu+ compounds are unstable in aqueous solution and undergo disproportionation.
2Cu+ → Cu2+ + Cu
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Community Answer
Many copper (I) compounds are unstable in aqueous solution and undergo...
Explanation:
Disproportionation is a redox reaction in which a compound oxidizes and reduces itself to form two different products having different oxidation states.
The given disproportionation reaction is:
2Cu+ → Cu + Cu2+
The reason for this disproportionation reaction is the negative free energy change of the reaction.
But, why does this reaction have a negative free energy change?
This is due to the second ionisation energy of Cu being higher than the first ionisation energy. This means that it requires more energy to remove the second electron from a copper ion than it does to remove the first electron.
Therefore, when a copper ion loses an electron, it becomes unstable because it has a partially-filled d-subshell. This instability is relieved when the copper ion gains another electron to form a Cu+ ion.
However, the Cu+ ion is also unstable because it has a partially-filled d-subshell. This instability is relieved when the Cu+ ion gains another electron to form a Cu2+ ion.
Thus, the disproportionation reaction occurs because both Cu+ and Cu2+ ions are unstable and want to gain or lose electrons to attain a stable electron configuration.
Additionally, the hydration energy of Cu is greater than that of Cu2+ because the Cu+ ion is smaller and has a higher charge density than the Cu2+ ion. This means that the Cu+ ion attracts water molecules more strongly than the Cu2+ ion. Therefore, the hydration energy of Cu is greater than that of Cu2+.
Disproportionation is a redox reaction in which a compound oxidizes and reduces itself to form two different products having different oxidation states.
The given disproportionation reaction is:
2Cu+ → Cu + Cu2+
The reason for this disproportionation reaction is the negative free energy change of the reaction.
But, why does this reaction have a negative free energy change?
This is due to the second ionisation energy of Cu being higher than the first ionisation energy. This means that it requires more energy to remove the second electron from a copper ion than it does to remove the first electron.
Therefore, when a copper ion loses an electron, it becomes unstable because it has a partially-filled d-subshell. This instability is relieved when the copper ion gains another electron to form a Cu+ ion.
However, the Cu+ ion is also unstable because it has a partially-filled d-subshell. This instability is relieved when the Cu+ ion gains another electron to form a Cu2+ ion.
Thus, the disproportionation reaction occurs because both Cu+ and Cu2+ ions are unstable and want to gain or lose electrons to attain a stable electron configuration.
Additionally, the hydration energy of Cu is greater than that of Cu2+ because the Cu+ ion is smaller and has a higher charge density than the Cu2+ ion. This means that the Cu+ ion attracts water molecules more strongly than the Cu2+ ion. Therefore, the hydration energy of Cu is greater than that of Cu2+.
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Many copper (I) compounds are unstable in aqueous solution and undergo disproportionation as 2Cu+ → Cu + Cu2+ . This is due toa)free energy change of reaction is positiveb)free energy of reaction is negativec)second ionisation energy of Cu is higher than first ionisation energyd)hydration energy of Cu+ is less than Cu2+Correct answer is option 'B'. Can you explain this answer? for Class 12 2026 is part of Class 12 preparation. The Question and answers have been prepared according to the Class 12 exam syllabus. Information about Many copper (I) compounds are unstable in aqueous solution and undergo disproportionation as 2Cu+ → Cu + Cu2+ . This is due toa)free energy change of reaction is positiveb)free energy of reaction is negativec)second ionisation energy of Cu is higher than first ionisation energyd)hydration energy of Cu+ is less than Cu2+Correct answer is option 'B'. Can you explain this answer? covers all topics & solutions for Class 12 2026 Exam. Find important definitions, questions, meanings, examples, exercises and tests below for Many copper (I) compounds are unstable in aqueous solution and undergo disproportionation as 2Cu+ → Cu + Cu2+ . This is due toa)free energy change of reaction is positiveb)free energy of reaction is negativec)second ionisation energy of Cu is higher than first ionisation energyd)hydration energy of Cu+ is less than Cu2+Correct answer is option 'B'. Can you explain this answer?.
Many copper (I) compounds are unstable in aqueous solution and undergo disproportionation as 2Cu+ → Cu + Cu2+ . This is due toa)free energy change of reaction is positiveb)free energy of reaction is negativec)second ionisation energy of Cu is higher than first ionisation energyd)hydration energy of Cu+ is less than Cu2+Correct answer is option 'B'. Can you explain this answer? for Class 12 2026 is part of Class 12 preparation. The Question and answers have been prepared according to the Class 12 exam syllabus. Information about Many copper (I) compounds are unstable in aqueous solution and undergo disproportionation as 2Cu+ → Cu + Cu2+ . This is due toa)free energy change of reaction is positiveb)free energy of reaction is negativec)second ionisation energy of Cu is higher than first ionisation energyd)hydration energy of Cu+ is less than Cu2+Correct answer is option 'B'. Can you explain this answer? covers all topics & solutions for Class 12 2026 Exam. Find important definitions, questions, meanings, examples, exercises and tests below for Many copper (I) compounds are unstable in aqueous solution and undergo disproportionation as 2Cu+ → Cu + Cu2+ . This is due toa)free energy change of reaction is positiveb)free energy of reaction is negativec)second ionisation energy of Cu is higher than first ionisation energyd)hydration energy of Cu+ is less than Cu2+Correct answer is option 'B'. Can you explain this answer?.
Solutions for Many copper (I) compounds are unstable in aqueous solution and undergo disproportionation as 2Cu+ → Cu + Cu2+ . This is due toa)free energy change of reaction is positiveb)free energy of reaction is negativec)second ionisation energy of Cu is higher than first ionisation energyd)hydration energy of Cu+ is less than Cu2+Correct answer is option 'B'. Can you explain this answer? in English & in Hindi are available as part of our courses for Class 12. Download more important topics, notes, lectures and mock test series for Class 12 Exam by signing up for free.
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