Iron is used as a catalyst in the Haber process, and this catalytic ability of transition metals is largely due to
Correct answer: B. their ability to change oxidation state and to adsorb reactants onto their surface
- A. their high density
- B. their ability to change oxidation state and to adsorb reactants onto their surface
- C. their low melting points
- D. the complete absence of d electrons
Explanation
Variable oxidation states allow a transition metal to accept and release electrons during a reaction, providing an alternative pathway of lower activation energy, and the partly filled d orbitals let gases bond weakly to the metal surface so that their bonds are stretched and weakened. Vanadium pentoxide in the Contact process and nickel in hydrogenation work in the same ways. Density and melting point have nothing to do with it.
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About Electronic Structure of d-Block Elements
The electronic structure of d-block elements covers the filling of the (n-1)d and ns orbitals, general electronic configurations, and the exceptions shown by chromium and copper. It explains how partially filled d orbitals produce variable oxidation states, coloured ions, magnetic behaviour and complex formation, while distinguishing transition elements from elements with completely filled d subshells.
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531 free Transition Elements MCQs from Chemistry, each with the correct answer and an explanation. Unlimited attempts, no account needed.
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