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Tamil Nadu Board of Secondary EducationHSC Science Class 12

Assertion: pure iron when heated in dry air is converted with a layer of rust. Reason: Rust has the compositionFe3O4.

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Question

Assertion: pure iron when heated in dry air is converted with a layer of rust.

Reason: Rust has the compositionFe3O4.

Options

  • if both assertion and reason are true and reason is the correct explanation of assertion.

  • if both assertion and reason are true but reason is not the correct explanation of assertion.

  • assertion is true but reason is false.

  • both assertion and reason are false.

MCQ
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Solution

both assertion and reason are false.

Explanation:

Both are false

  1. Dry air has no reaction with iron
  2. Rust has the composition \[\ce{Fe2O3.{x} H2O}\]
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Chapter 9: Electro Chemistry - Evaluation [Page 64]

APPEARS IN

Samacheer Kalvi Chemistry - Volume 1 and 2 [English] Class 12 TN Board
Chapter 9 Electro Chemistry
Evaluation | Q 15. | Page 64

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