Why do the transition elements exhibits variable oxidation states?
In transition elements, the $d$-orbitals are incompletely occupied in such a way that there oxidation state differs by unity.
The general electronic configuration of transition elements is $(n-1) d^{1-10} n s^{1-2}$. Due to very less difference in the energies of ( $n-1$ ) $d$-orbitals and $n s$-orbitals, the transition elements exhibit more than one oxidation states as electrons of both these shells can participate in chemical bonding. The $4 s$-electrons are responsible for lower oxidation state while both $3 d$ and $4 s$ electrons are responsible for higher oxidation states in first transition series.
The $3d-$ metal ions are paramagnetic in nature because
Amongest following the lowest degree of paramagnetism per mole of the compound at $298 K$ will be shown by
Which of the following statements is not true in regard to transition elements
In $d-$ block $3d$ series, which of the following element has maximum size ?
Which of the following is more paramagnetic