Q33 P - Chemistry: Molecular Nature Of Matter And Change

Question

Cerium (Ce) and ytterbium (Yb) exhibit some oxidation states in addition to +3. 

(a) Write the electron configurations of Ce²⁺ , Ce³⁺ and Ce⁴⁺ . 

(b) Write the electron configurations of Yb²⁺ , Yb²⁺ and Yb⁴⁺ . 

(c) In addition to the 3+ ions, the ions Ce⁴⁺ and Yb²⁺ are stable. Suggest a reason for this stability.

Step-by-Step Solution

Answer

a) the electron configurations of $C{e}^{2+}:\left[Xe\right]4f^{1}5d^{1}C{e}^{3+}:\left[Xe\right]4f^{1}C{e}^{4+}:\left[Xe\right]4f^0$

b) the electron configurations of $Y{b}^{2+}:\left[Xe\right]4f^{14}Y{b}^{3+}:\left[Xe\right]4f^{13}Y{b}^{4+}:\left[Xe\right]4f^{12}$

c) Ce⁴⁺ and Yb²⁺ are stable because Ce⁴⁺ has empty ( f⁰ )and stable 4f subshell and Yb²⁺ has stable filled (f¹⁴) 4f subshell

Step 1: Electron configurations

The electron configuration is that the distribution of electrons of an atom or molecule (or other physical structure) in atomic or molecular orbitals.

Step 2: The electron configuration of each element

a) Electron configuration of element Ce

1s²2s²2p⁶3s²3p⁶3d¹⁰4s²4p⁶4d¹⁰5s²5p⁶4f¹5d¹6s²

b) Electron configuration of elemental Yb: 

1s²2s²2p⁶3s²3p⁶3d¹⁰4s²4p⁶4d¹⁰5s²5p⁶4f¹⁴5d⁰6s²

c) Ce⁴⁺ and Yb²⁺ are stable because Ce⁴⁺ has empty ( f⁰) and stable 4f subshell and Yb²⁺ has stable filled ( f¹⁴) subshell.