Assertion (A): Graphite is a good conductor of electricity. Reason (R): In graphite, each carbon atom uses three of its valence electrons to form covalent bonds, leaving one free delocalized electron. MCQ with Answer and Explanation

Assertion (A): Graphite is a good conductor of electricity. Reason (R): In graphite, each carbon atom uses three of its valence electrons to form covalent bonds, leaving one free delocalized electron.
A. A is true, but R is false
B. A is false, but R is true
C. Both A and R are true, but R is not the correct explanation of A
D. Both A and R are true, and R is the correct explanation of A
Answer: Option D
Solution (By JKExamLibrary)
Graphite has a layered structure where each carbon is sp² hybridized, forming three sigma bonds with neighboring carbons, leaving one unhybridized p orbital electron delocalized over the entire layer. These mobile electrons allow electrical conduction parallel to layers. Diamond, with all four electrons in covalent bonds, is an insulator. Both the assertion and reason are correct, and the reason correctly explains the conductivity of graphite.

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During electrolysis of water, hydrogen is liberated at:
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B. Anode
C. Salt bridge
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Correct Answer: Option D


Explanation:
Cathode (negative electrode): 2H₂O + 2e⁻ → H₂ + 2OH⁻ (or 2H⁺ + 2e⁻ → H₂). Hydrogen gas is collected at the cathode. At the anode, oxygen is produced: 2H₂O → O₂ + 4H⁺ + 4e⁻. The volume of H₂ is double that of O₂.

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In electroplating, the metal to be plated is made the:
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Correct Answer: Option B


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Question #3
A solution with a pH of 2 is how many times more acidic than a solution with a pH of 5?
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Correct Answer: Option B


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