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

Gujarat BoardEnglish MediumSTD 12 ScienceChemistry4. d and f- block elements1 Mark
MCQ
For the following Assertion and Reason, the correct option is

Assertion : For hydrogenation reactions, the catalytic activity increases from Group $5$ to Group $11$ metals with maximum activity shown by Group $7-9$ elements.

Reason : The reactants are most strongly adsorbed on group $7-9 $ elements.

  • A
    Both assertion and reason are true but the reason is not the correct explanation for the assertion.
  • B
    Both assertion and reason are false.
  • C
    Both assertion and reason are true and the reason is the correct explanation for the assertion.
  • ✓
    The assertion is true, but the reason is false.
✓

Answer

Correct option: D.
The assertion is true, but the reason is false.
d

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