d and f Block Elements

Groups 1 and 2

Groups 13 to 18

Groups 3 to 12

Groups 1 to 12

$(n-1)d^{1-10} ns^{1-2}$

$(n-1)d^{1-5} ns^1$

$nd^{1-10} ns^2$

$(n-2)f^{1-14} (n-1)d^{0-1} ns^2$

$[Ar] 3d^4 4s^2$

$[Ar] 3d^5 4s^1$

$[Ar] 3d^6 4s^0$

$[Ar] 4s^2 4p^4$

Paired electrons in the d-orbitals

High nuclear charge

Unpaired electrons in the d-orbitals

Empty d-orbitals

They have high melting and boiling points.

They have a completely filled d-subshell in their ground state and common oxidation states.

They do not form any complex compounds.

They are found in the s-block of the periodic table.

$Ti^{3+}$

$Cu^{2+}$

$Sc^{3+}$

$V^{3+}$

The ionic radius increases with the increase in atomic number.

The ionic radius decreases with the increase in atomic number.

The ionic radius first increases and then decreases.

There is no significant change in the ionic radius.

$4f$ electrons

$5d$ electrons

$6s$ electrons

$4p$ electrons

The shielding effect of $d$-electrons.

Lanthanoid contraction.

Increase in the number of valence electrons.

Decreased effective nuclear charge.

The electron must be removed from a stable, fully filled $3d^{10}$ configuration

Zinc has the largest atomic size in the $3d$ series

The effective nuclear charge of Zinc is the lowest in the series

Zinc has a half-filled $4s$ orbital in its $+2$ state

$Cr$

$Fe$

$Mn$

$V$

Increase in the atomic radius

Decrease in the nuclear charge

Increase in the effective nuclear charge

Increase in the shielding effect of $4s$ electrons

Form stable ionic bonds with all reactants

Maintain a fixed oxidation state throughout the reaction

Exist in a gaseous state at high temperatures

Show variable oxidation states and provide a large surface area for adsorption

$Sc^{3+}$

$Ti^{3+}$

$Cr^{3+}$

$Cu^{2+}$

$MnO_2$

$Fe_2O_3$

$V_2O_5$

$Cr_2O_3$

Octahedral

Tetrahedral

Square Planar

Trigonal Bipyramidal

Chromite

Bauxite

Pyrolusite

Hematite

Reduction of Chromium from +6 to +3

Formation of the dichromate ion due to a change in pH

Oxidation of Chromium from +3 to +6

Formation of a complex with water molecules

$[Xe] 4f^{1-14} 5d^{0-1} 6s^2$

$[Rn] 5f^{1-14} 6d^{0-1} 7s^2$

$[Xe] 4f^{0-14} 5d^{10} 6s^2$

$[Kr] 4d^{10} 5s^{1} 5p^6$

Cerium ($Z=58$)

Promethium ($Z=61$)

Thorium ($Z=90$)

Terbium ($Z=65$)

Poor shielding effect of $4f$ electrons

Effective shielding by $4f$ electrons

Decrease in effective nuclear charge

Increase in the number of $5d$ electrons

Increases significantly

Remains constant

Increases then decreases

Decreases steadily

$+3$

$+2$

$+4$

$+5$

$Ti$ and $Zr$

$Zr$ and $Hf$

$Nb$ and $Ta$

$Mo$ and $W$