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Pick out the correct statement(s)
- a)MnO2 dissolves in conc. HCl, but does not form Mn4+ ions.
- b)Decomposition of acidic KMnO4 is catalysed by sunlight.
- c)MnO2−4 is oxidising and stable only in very strong alkali. In dilute alkali, water or acidic solutions it disproportionates.
- d)KMnO4 does not act as an oxidising agent in alkaline medium.
Correct answer is option 'A,B,C'. Can you explain this answer?
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Most Upvoted Answer
Pick out the correct statement(s)a)MnO2 dissolves in conc. HCl, but d...
Explanation:
a) MnO2 dissolves in conc. HCl, but does not form Mn4+ ions:
When MnO2 is dissolved in concentrated HCl (hydrochloric acid), it undergoes the following reaction:
MnO2 + 4HCl → MnCl2 + Cl2 + 2H2O
In this reaction, MnO2 is reduced to Mn2+ ions, and chlorine gas (Cl2) is evolved. Therefore, MnO2 does not form Mn4+ ions in this reaction.
b) Decomposition of acidic KMnO4 is catalyzed by sunlight:
When acidic KMnO4 (potassium permanganate) is exposed to sunlight, it undergoes photochemical decomposition. Sunlight provides the energy required for the decomposition reaction to occur. The reaction can be represented as follows:
2KMnO4 + H2SO4 → K2SO4 + 2MnO2 + 2H2O + [3O2]
In this reaction, KMnO4 is reduced to MnO2, and oxygen gas (O2) is evolved. The presence of sunlight speeds up this decomposition reaction.
c) MnO2−4 is oxidizing and stable only in very strong alkali. In dilute alkali, water or acidic solutions, it disproportionates:
MnO2−4 refers to the manganate ion (MnO4) with a charge of -2. In very strong alkali solutions, MnO2−4 is stable and acts as an oxidizing agent. However, in dilute alkali, water, or acidic solutions, it undergoes disproportionation. Disproportionation refers to a redox reaction where a species is simultaneously oxidized and reduced. The reaction can be represented as follows:
3MnO4− + 4H2O → 2MnO4−2 + MnO2 + 8OH−
In this reaction, some of the manganate ions are reduced to manganate (MnO4−2) ions, while others are oxidized to MnO2. The reaction occurs in dilute alkali, water, or acidic solutions due to the presence of suitable reducing agents or oxidizing agents.
d) KMnO4 does not act as an oxidizing agent in alkaline medium:
In an alkaline medium, KMnO4 (potassium permanganate) does not act as a strong oxidizing agent. It undergoes reduction to form MnO2, but the reaction is not as vigorous as in acidic medium. In alkaline medium, other oxidizing agents such as hydrogen peroxide (H2O2) are more effective. Therefore, KMnO4 is not commonly used as an oxidizing agent in alkaline solutions.
Conclusion:
The correct statements are:
a) MnO2 dissolves in conc. HCl, but does not form Mn4+ ions.
b) Decomposition of acidic KMnO4 is catalyzed by sunlight.
c) MnO2−4 is oxidizing and stable only in very strong alkali. In dilute alkali, water, or acidic solutions, it disproportionates.
Statement d) is incorrect as KMnO4 does not act as an oxidizing agent in
a) MnO2 dissolves in conc. HCl, but does not form Mn4+ ions:
When MnO2 is dissolved in concentrated HCl (hydrochloric acid), it undergoes the following reaction:
MnO2 + 4HCl → MnCl2 + Cl2 + 2H2O
In this reaction, MnO2 is reduced to Mn2+ ions, and chlorine gas (Cl2) is evolved. Therefore, MnO2 does not form Mn4+ ions in this reaction.
b) Decomposition of acidic KMnO4 is catalyzed by sunlight:
When acidic KMnO4 (potassium permanganate) is exposed to sunlight, it undergoes photochemical decomposition. Sunlight provides the energy required for the decomposition reaction to occur. The reaction can be represented as follows:
2KMnO4 + H2SO4 → K2SO4 + 2MnO2 + 2H2O + [3O2]
In this reaction, KMnO4 is reduced to MnO2, and oxygen gas (O2) is evolved. The presence of sunlight speeds up this decomposition reaction.
c) MnO2−4 is oxidizing and stable only in very strong alkali. In dilute alkali, water or acidic solutions, it disproportionates:
MnO2−4 refers to the manganate ion (MnO4) with a charge of -2. In very strong alkali solutions, MnO2−4 is stable and acts as an oxidizing agent. However, in dilute alkali, water, or acidic solutions, it undergoes disproportionation. Disproportionation refers to a redox reaction where a species is simultaneously oxidized and reduced. The reaction can be represented as follows:
3MnO4− + 4H2O → 2MnO4−2 + MnO2 + 8OH−
In this reaction, some of the manganate ions are reduced to manganate (MnO4−2) ions, while others are oxidized to MnO2. The reaction occurs in dilute alkali, water, or acidic solutions due to the presence of suitable reducing agents or oxidizing agents.
d) KMnO4 does not act as an oxidizing agent in alkaline medium:
In an alkaline medium, KMnO4 (potassium permanganate) does not act as a strong oxidizing agent. It undergoes reduction to form MnO2, but the reaction is not as vigorous as in acidic medium. In alkaline medium, other oxidizing agents such as hydrogen peroxide (H2O2) are more effective. Therefore, KMnO4 is not commonly used as an oxidizing agent in alkaline solutions.
Conclusion:
The correct statements are:
a) MnO2 dissolves in conc. HCl, but does not form Mn4+ ions.
b) Decomposition of acidic KMnO4 is catalyzed by sunlight.
c) MnO2−4 is oxidizing and stable only in very strong alkali. In dilute alkali, water, or acidic solutions, it disproportionates.
Statement d) is incorrect as KMnO4 does not act as an oxidizing agent in
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Community Answer
Pick out the correct statement(s)a)MnO2 dissolves in conc. HCl, but d...
2. Decomposition of acidified KMnO4 is catalysed by sunlight.
3.
4. KMnO4 also acts as an oxidizing agent in alkaline medium:
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Pick out the correct statement(s)a)MnO2 dissolves in conc. HCl, but does not form Mn4+ ions.b)Decomposition of acidic KMnO4 is catalysed by sunlight.c)MnO2−4 is oxidising and stable only in very strong alkali. In dilute alkali, water or acidic solutions it disproportionates.d)KMnO4 does not act as an oxidising agent in alkaline medium.Correct answer is option 'A,B,C'. Can you explain this answer?
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Pick out the correct statement(s)a)MnO2 dissolves in conc. HCl, but does not form Mn4+ ions.b)Decomposition of acidic KMnO4 is catalysed by sunlight.c)MnO2−4 is oxidising and stable only in very strong alkali. In dilute alkali, water or acidic solutions it disproportionates.d)KMnO4 does not act as an oxidising agent in alkaline medium.Correct answer is option 'A,B,C'. Can you explain this answer? for JEE 2024 is part of JEE preparation. The Question and answers have been prepared according to the JEE exam syllabus. Information about Pick out the correct statement(s)a)MnO2 dissolves in conc. HCl, but does not form Mn4+ ions.b)Decomposition of acidic KMnO4 is catalysed by sunlight.c)MnO2−4 is oxidising and stable only in very strong alkali. In dilute alkali, water or acidic solutions it disproportionates.d)KMnO4 does not act as an oxidising agent in alkaline medium.Correct answer is option 'A,B,C'. Can you explain this answer? covers all topics & solutions for JEE 2024 Exam. Find important definitions, questions, meanings, examples, exercises and tests below for Pick out the correct statement(s)a)MnO2 dissolves in conc. HCl, but does not form Mn4+ ions.b)Decomposition of acidic KMnO4 is catalysed by sunlight.c)MnO2−4 is oxidising and stable only in very strong alkali. In dilute alkali, water or acidic solutions it disproportionates.d)KMnO4 does not act as an oxidising agent in alkaline medium.Correct answer is option 'A,B,C'. Can you explain this answer?.
Pick out the correct statement(s)a)MnO2 dissolves in conc. HCl, but does not form Mn4+ ions.b)Decomposition of acidic KMnO4 is catalysed by sunlight.c)MnO2−4 is oxidising and stable only in very strong alkali. In dilute alkali, water or acidic solutions it disproportionates.d)KMnO4 does not act as an oxidising agent in alkaline medium.Correct answer is option 'A,B,C'. Can you explain this answer? for JEE 2024 is part of JEE preparation. The Question and answers have been prepared according to the JEE exam syllabus. Information about Pick out the correct statement(s)a)MnO2 dissolves in conc. HCl, but does not form Mn4+ ions.b)Decomposition of acidic KMnO4 is catalysed by sunlight.c)MnO2−4 is oxidising and stable only in very strong alkali. In dilute alkali, water or acidic solutions it disproportionates.d)KMnO4 does not act as an oxidising agent in alkaline medium.Correct answer is option 'A,B,C'. Can you explain this answer? covers all topics & solutions for JEE 2024 Exam. Find important definitions, questions, meanings, examples, exercises and tests below for Pick out the correct statement(s)a)MnO2 dissolves in conc. HCl, but does not form Mn4+ ions.b)Decomposition of acidic KMnO4 is catalysed by sunlight.c)MnO2−4 is oxidising and stable only in very strong alkali. In dilute alkali, water or acidic solutions it disproportionates.d)KMnO4 does not act as an oxidising agent in alkaline medium.Correct answer is option 'A,B,C'. Can you explain this answer?.
Solutions for Pick out the correct statement(s)a)MnO2 dissolves in conc. HCl, but does not form Mn4+ ions.b)Decomposition of acidic KMnO4 is catalysed by sunlight.c)MnO2−4 is oxidising and stable only in very strong alkali. In dilute alkali, water or acidic solutions it disproportionates.d)KMnO4 does not act as an oxidising agent in alkaline medium.Correct answer is option 'A,B,C'. Can you explain this answer? in English & in Hindi are available as part of our courses for JEE.
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Here you can find the meaning of Pick out the correct statement(s)a)MnO2 dissolves in conc. HCl, but does not form Mn4+ ions.b)Decomposition of acidic KMnO4 is catalysed by sunlight.c)MnO2−4 is oxidising and stable only in very strong alkali. In dilute alkali, water or acidic solutions it disproportionates.d)KMnO4 does not act as an oxidising agent in alkaline medium.Correct answer is option 'A,B,C'. Can you explain this answer? defined & explained in the simplest way possible. Besides giving the explanation of
Pick out the correct statement(s)a)MnO2 dissolves in conc. HCl, but does not form Mn4+ ions.b)Decomposition of acidic KMnO4 is catalysed by sunlight.c)MnO2−4 is oxidising and stable only in very strong alkali. In dilute alkali, water or acidic solutions it disproportionates.d)KMnO4 does not act as an oxidising agent in alkaline medium.Correct answer is option 'A,B,C'. Can you explain this answer?, a detailed solution for Pick out the correct statement(s)a)MnO2 dissolves in conc. HCl, but does not form Mn4+ ions.b)Decomposition of acidic KMnO4 is catalysed by sunlight.c)MnO2−4 is oxidising and stable only in very strong alkali. In dilute alkali, water or acidic solutions it disproportionates.d)KMnO4 does not act as an oxidising agent in alkaline medium.Correct answer is option 'A,B,C'. Can you explain this answer? has been provided alongside types of Pick out the correct statement(s)a)MnO2 dissolves in conc. HCl, but does not form Mn4+ ions.b)Decomposition of acidic KMnO4 is catalysed by sunlight.c)MnO2−4 is oxidising and stable only in very strong alkali. In dilute alkali, water or acidic solutions it disproportionates.d)KMnO4 does not act as an oxidising agent in alkaline medium.Correct answer is option 'A,B,C'. Can you explain this answer? theory, EduRev gives you an
ample number of questions to practice Pick out the correct statement(s)a)MnO2 dissolves in conc. HCl, but does not form Mn4+ ions.b)Decomposition of acidic KMnO4 is catalysed by sunlight.c)MnO2−4 is oxidising and stable only in very strong alkali. In dilute alkali, water or acidic solutions it disproportionates.d)KMnO4 does not act as an oxidising agent in alkaline medium.Correct answer is option 'A,B,C'. Can you explain this answer? tests, examples and also practice JEE tests.
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