CUET · CHEMISTRY · PYQ PAPER 2025
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There are mainly four series of the transition metals, \(3 d\) series ( \(S c\) to Zn), \(4 d\) series (Y to Cd), 5d series (La and Hf to Hg) and 6d series which has \(A c\) and elements from Rf to Cn. The two series of the inner transition metals; \(4 f\) (Ce to Lu) and \(5 f\) (Th to Lr) are known as lanthanoids and actinoids respectively. Their chemical properties are transitional between those of \(s\) and p-block elements. The transition metals (with the exception of Zn, Cd and Hg) are very hard and have low volatility. Their melting and boiling points are high. Transition metals have incomplete d subshell either in neutral atom or in their ions. With partly filled d orbitals these elements exhibit certain characteristic properties such as display of a variety of oxidation states, formation of coloured ions and entering into complex formation with a variety of ligands. The transition metals and their compounds are known for their catalytic activity.
In series Sc to Zn, the lowest enthalpy of atomization is shown by
- A Sc
- B Zn
- C Mn
- D Co
Answer & Solution
Correct Answer
(B) Zn
Step-by-step Solution
Detailed explanation
Zn
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