This category explains the electronic configurations of lanthanoids and the phenomenon of lanthanoid contraction. It is designed to help students grasp these key concepts in chemistry.
Tungsten (W) has the highest melting point among transition metals (3422°C).
Ref: NCERT Class 12 Chemistry > Chapter 4: d and f Block Elements > Topic: Lanthanoids - Electronic Configuration and Lanthanoid Contraction
Interstitial compounds are formed when small atoms occupy voids in metal crystal lattices.
Ref: NCERT Class 12 Chemistry > Chapter 4: d and f Block Elements > Topic: Lanthanoids - Electronic Configuration and Lanthanoid Contraction
Cu + is common due to the stability of the 3d 10 configuration.
Ref: NCERT Class 12 Chemistry > Chapter 4: d and f Block Elements > Topic: Lanthanoids - Electronic Configuration and Lanthanoid Contraction
Lanthanoids are not highly volatile; they have high melting points.
Ref: NCERT Class 12 Chemistry > Chapter 4: d and f Block Elements > Topic: Lanthanoids - Electronic Configuration and Lanthanoid Contraction
Cerium (Ce) exhibits +4 oxidation state due to the stability of empty 4f orbitals (4f 0 ).
Ref: NCERT Class 12 Chemistry > Chapter 4: d and f Block Elements > Topic: Lanthanoids - Electronic Configuration and Lanthanoid Contraction
MnO 4 – oxidizes Fe 2+ to Fe 3+ and itself reduces to Mn 2+ .
Ref: NCERT Class 12 Chemistry > Chapter 4: d and f Block Elements > Topic: Lanthanoids - Electronic Configuration and Lanthanoid Contraction
Lanthanoid contraction causes similar atomic radii of Zr (160 pm) and Hf (159 pm), making their separation difficult.
Ref: NCERT Class 12 Chemistry > Chapter 4: d and f Block Elements > Topic: Lanthanoids - Electronic Configuration and Lanthanoid Contraction
Lanthanoid contraction causes similar atomic sizes of 4d and 5d transition elements.
Ref: NCERT Class 12 Chemistry > Chapter 4: d and f Block Elements > Topic: Lanthanoids - Electronic Configuration and Lanthanoid Contraction
Lanthanoid contraction is the gradual decrease in atomic/ionic radii across the lanthanoid series.
Ref: NCERT Class 12 Chemistry > Chapter 4: d and f Block Elements > Topic: Lanthanoids - Electronic Configuration and Lanthanoid Contraction
Yb 2+ has f 14 configuration which is stable due to completely filled f-orbitals.
Ref: NCERT Class 12 Chemistry > Chapter 4: d and f Block Elements > Topic: Lanthanoids - Electronic Configuration and Lanthanoid Contraction
Let oxidation state of Cr be x. 2(+1) + 2x + 7(-2) = 0 → x = +6.
Ref: NCERT Class 12 Chemistry > Chapter 4: d and f Block Elements > Topic: Lanthanoids - Electronic Configuration and Lanthanoid Contraction
Sc 3+ has no unpaired electrons (3d 0 ), so it does not exhibit d-d transitions.
Ref: NCERT Class 12 Chemistry > Chapter 4: d and f Block Elements > Topic: Lanthanoids - Electronic Configuration and Lanthanoid Contraction
