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AIIMS2018Chemistryp Block Elements (Group 15, 16, 17 & 18)

Assertion : Red phosphorus on heating changes its colour into black. Reason : Black phosphorus contains P ₄ units.

Options

  1. AIf both assertion and reason are true and reason is the correct explanation of assertion.
  2. BIf both assertion and reason are true but reason is not the correct explanation of assertion.
  3. CIf assertion is true but reason is false.
  4. DIf both assertion and reason are false.

Correct answer

C. If assertion is true but reason is false.

Step-by-step solution

Black phosphorus has graphite like network structure.

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