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STD 12 - 4. d and f- block elements — JEE STD 11 Science — Question

Gujarat BoardEnglish MediumSTD 11 ScienceJEESTD 12 - 4. d and f- block elements4 Marks
MCQ
Assertion : Transition metals show variable valency.

Reason : Transition metals have a large energy difference between the $ns^2$ and $(n -1)d$ electrons.

  • A
    If both Assertion and Reason are correct and the Reason is a correct explanation of the Assertion.
  • B
    If both Assertion and Reason are correct but Reason is not a correct explanation of the Assertion.
  • ✓
    If the Assertion is correct but Reason is incorrect.
  • D
    If both the Assertion and Reason are incorrect.
✓

Answer

Correct option: C.
If the Assertion is correct but Reason is incorrect.
c
The assertion is correct but the reason is false. Actually transition metal show  variable valency due to very small difference between the $ns^2$ and $(n -1)d$ electrons.

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