D and F block NOTES MBBS Notes | EduRev

MBBS : D and F block NOTES MBBS Notes | EduRev

 Page 1


8
The d & f-Block 
Elements
Electronic Configurations/ (n–1) d
1–10 
ns
1–2
.
Exceptions: 1. Cr = 4s
1
 3d
5
       2. Cu = 4s
1
 3d
10
       3. Pd = 5s
0
4d
10
Transition Series
1
st
3d series Sc
21
 - Zn
30
 9 + 1 = 10
2
nd
4d series Y
39
 - Cd
48
 9 + 1 = 10
3
rd
5d series La
57
, Hf
72 
- Hg
80
 9 + 1 = 10
4
th
6d series Ac
89
, Unq
104
- Uub
112
 9 + 1 = 10
General Properties of Transition 
Element
 
The transition elements exhibit typical 
characteristic properties due to their small atomic 
sizes, large nuclear charges and the presence of 
unpaired d - electrons.
 
Enthalpy of atomization: V > Ti > Ni > Co > Fe > 
Cr > Cu > Sc > Mn > Zn
(1) Trends in M.P of transition elements(TE)
 
In any row the melting points of these metals rise 
to a maximum at d
5
 except for anomalous values 
of Mn and Tc and fall regularly as the atomic 
number increases. They have high enthalpies of 
atomization. The maxima at about the middle of 
each series indicate that one unpaired electron 
per d orbital is particularly favorable for strong 
interatomic interaction.
Number of valence electrons increase
?
strong bonding
?
higher enthalpy of atomisation
 ?
higher boiling point
?
higher standard electronic potential
?
More noble character
M.P./10 K
3
Hf
Ta
W
Re
Os
Ir
Pt
Nb
Mo
Ru
Tc
Zr
Ti
V
Cr
Rh
Fe
Mn
Co
Pd
Ni
Cu
Au
Ag
Atomic number
Trends in melting points of
transition elements
1
2
3
4
After chromium, the number of unpaired electrons 
goes on decreasing. Accordingly, the melting points 
decrease after middle (Cr) because of increasing 
pairing of electrons.
(2) Size of atoms and ions
 
The covalent radii of the elements decreases from 
left to right across a row in the transition series, 
until near the end when the size increases slightly.
 
Metallic radii: Sc > Ti > Mn = Zn > V > Cr > Cu>  
Co = Ni
(3) Ionization Energies of 3d Series
 
IP values generally increase from left to right in 
any series but the increase is less than that of s 
block elements due to increase in nuclear charge is 
opposed by screening effect.
 
Ionization Enthalpy:  Zn > Fe > Co > Cu > Ni > 
Mn > Ti > Cr > V >Sc
Page 2


8
The d & f-Block 
Elements
Electronic Configurations/ (n–1) d
1–10 
ns
1–2
.
Exceptions: 1. Cr = 4s
1
 3d
5
       2. Cu = 4s
1
 3d
10
       3. Pd = 5s
0
4d
10
Transition Series
1
st
3d series Sc
21
 - Zn
30
 9 + 1 = 10
2
nd
4d series Y
39
 - Cd
48
 9 + 1 = 10
3
rd
5d series La
57
, Hf
72 
- Hg
80
 9 + 1 = 10
4
th
6d series Ac
89
, Unq
104
- Uub
112
 9 + 1 = 10
General Properties of Transition 
Element
 
The transition elements exhibit typical 
characteristic properties due to their small atomic 
sizes, large nuclear charges and the presence of 
unpaired d - electrons.
 
Enthalpy of atomization: V > Ti > Ni > Co > Fe > 
Cr > Cu > Sc > Mn > Zn
(1) Trends in M.P of transition elements(TE)
 
In any row the melting points of these metals rise 
to a maximum at d
5
 except for anomalous values 
of Mn and Tc and fall regularly as the atomic 
number increases. They have high enthalpies of 
atomization. The maxima at about the middle of 
each series indicate that one unpaired electron 
per d orbital is particularly favorable for strong 
interatomic interaction.
Number of valence electrons increase
?
strong bonding
?
higher enthalpy of atomisation
 ?
higher boiling point
?
higher standard electronic potential
?
More noble character
M.P./10 K
3
Hf
Ta
W
Re
Os
Ir
Pt
Nb
Mo
Ru
Tc
Zr
Ti
V
Cr
Rh
Fe
Mn
Co
Pd
Ni
Cu
Au
Ag
Atomic number
Trends in melting points of
transition elements
1
2
3
4
After chromium, the number of unpaired electrons 
goes on decreasing. Accordingly, the melting points 
decrease after middle (Cr) because of increasing 
pairing of electrons.
(2) Size of atoms and ions
 
The covalent radii of the elements decreases from 
left to right across a row in the transition series, 
until near the end when the size increases slightly.
 
Metallic radii: Sc > Ti > Mn = Zn > V > Cr > Cu>  
Co = Ni
(3) Ionization Energies of 3d Series
 
IP values generally increase from left to right in 
any series but the increase is less than that of s 
block elements due to increase in nuclear charge is 
opposed by screening effect.
 
Ionization Enthalpy:  Zn > Fe > Co > Cu > Ni > 
Mn > Ti > Cr > V >Sc
2
Most Wanted
(4) Oxidation State
Transition elements exhibit variable oxidation st ate 
due to small energy difference of ns and (n – 1)d 
electrons.
 
Sc(+3) and Zn(+2) exhibit only one oxidation state
 
Common oxidation state is +2
 
3d series highest oxidation state is +7 (Mn)
 
In d-block series highest oxidation state is +8 (Os, Ru)
In carbonyl compound oxidation state of metals is 
zero due to synergic effects.
The common examples are [Ni(CO)
4
], [Fe(CO)
5
] in 
which nickel and iron are in zero oxidation state.
 
Their higher oxidation states are more stable in 
fluoride and oxides.
 
Higher oxidation states in oxides are normally more 
stable than fluorides due to capability of oxygen to 
form multiple bonds.
Some more stable oxidation states of d-block 
elements
Cu + 2 Mn + 2 Pt + 4 Ag + 1
Cu + 3 Sc + 3 Au + 3 Ni + 2
Common oxidation states
Ti (+ 4) V (+5) Cr (+3, +5) Mn (+2, +4, +7)
Fe(+2, +3) Co (+2, +3) Ni (+2) Pt(+2, +4)
In p-block lower oxidation states of heavier elements 
are more stable while in d-block heavier element, 
higher oxidation state are more stable.
(5) Electrode potentials and chemical reactivity
Trends in the M
2+
/M Standard electro potential
 
S.R.P of M
+2
/M values increases from left to right 
as IP values increases. (except Zn)
Cu cannot displace H
2
 from acids because it has 
highest S.R.P value which is +0.34 V .
 
Mn, Ni and Zn have more negative S.R.P values 
than expected because.
 
Reason: Mn & Zn have d
5
 & d
10
 stable electronic 
configuration Ni has highest hydration energy.
 (DH
Hyd
 Ni
+2
 = –2121 kJ/mole)
Trends in the M
3+
/M
2+
 Standard electro potential
 
32
0
M /M
E
++ in the 3d series are observed for some 
metals are
Co
+3
/Co
+2
 > Mn
+3
/Mn
+2
> Fe
+3
/Fe
+2 
> Ti
+3
/Ti
+2 
> 
Sc
+3
/Sc
+2
>V
+3
/V
+2
(6) Magnetic Property of Transition Metals
 
Paramagnetic substances contain unpaired electron 
spins or unpaired electrons.
 
Ex : K
3
[Fe(CN)
6
], Sc
2+
, Cr
3+
 etc
 
Diamagnetic substances exhibit decrease in weight 
in the presence of magnetic field.
 
Ex.: Ti
+4
, V
+5
 , Sc
3+
, Zn, Hg, Cd etc
 
Diamagnetic substances contain electron pairs with 
opposite spins.
 
Ferromagnetic substances are considered as a 
special case of paramagnetic substances.
 
Paramagnetism of substances (molecules, atoms or 
ions)is due to the spins of the unpaired electrons 
and also due to angular orbital momentum.
In terms of number of unpaired electrons (n), the 
magnetic moment is given by the formula.
 ( )
s
nn 2 µ= + BM
 Q. The magnetic moment of Ni
2+
 ion (atomic 
number of Ni = 28) in BM unit is:
a. 1.73 b. 4.81
c. 5.96 d. 2.84
 Ans. (d) Ni
28
 = [Ar] 3d
8
 , 4s
2
Ni
2+
 = [Ar] 3d
8 
? n = 2
n(n 2) 2(2 2) 2(4) 8 2.84BM µ= += += = =
 Q. The correct order of magnetic moments (spin 
only values in B.M.) among is
a. [Fe(CN)
6
]
4–
 > [MnCl
4
]
2–
 > [CoCl
4
]
2–
b. [MnCl
4
]
2–
 > [Fe(CN)
6
]
4–
 > [CoCl
4
]
2–
c. [MnCl
4
]
2–
 > [CoCl
4
]
2–
 > [Fe(CN)
6
]
4–
d. [Fe(CN)
6
]
4–
 > [CoCl
4
]
2–
 > [MnCl
4
]
2–
 Ans. (c) 
        
SCAN (Special Cases Asked in NEET)
Page 3


8
The d & f-Block 
Elements
Electronic Configurations/ (n–1) d
1–10 
ns
1–2
.
Exceptions: 1. Cr = 4s
1
 3d
5
       2. Cu = 4s
1
 3d
10
       3. Pd = 5s
0
4d
10
Transition Series
1
st
3d series Sc
21
 - Zn
30
 9 + 1 = 10
2
nd
4d series Y
39
 - Cd
48
 9 + 1 = 10
3
rd
5d series La
57
, Hf
72 
- Hg
80
 9 + 1 = 10
4
th
6d series Ac
89
, Unq
104
- Uub
112
 9 + 1 = 10
General Properties of Transition 
Element
 
The transition elements exhibit typical 
characteristic properties due to their small atomic 
sizes, large nuclear charges and the presence of 
unpaired d - electrons.
 
Enthalpy of atomization: V > Ti > Ni > Co > Fe > 
Cr > Cu > Sc > Mn > Zn
(1) Trends in M.P of transition elements(TE)
 
In any row the melting points of these metals rise 
to a maximum at d
5
 except for anomalous values 
of Mn and Tc and fall regularly as the atomic 
number increases. They have high enthalpies of 
atomization. The maxima at about the middle of 
each series indicate that one unpaired electron 
per d orbital is particularly favorable for strong 
interatomic interaction.
Number of valence electrons increase
?
strong bonding
?
higher enthalpy of atomisation
 ?
higher boiling point
?
higher standard electronic potential
?
More noble character
M.P./10 K
3
Hf
Ta
W
Re
Os
Ir
Pt
Nb
Mo
Ru
Tc
Zr
Ti
V
Cr
Rh
Fe
Mn
Co
Pd
Ni
Cu
Au
Ag
Atomic number
Trends in melting points of
transition elements
1
2
3
4
After chromium, the number of unpaired electrons 
goes on decreasing. Accordingly, the melting points 
decrease after middle (Cr) because of increasing 
pairing of electrons.
(2) Size of atoms and ions
 
The covalent radii of the elements decreases from 
left to right across a row in the transition series, 
until near the end when the size increases slightly.
 
Metallic radii: Sc > Ti > Mn = Zn > V > Cr > Cu>  
Co = Ni
(3) Ionization Energies of 3d Series
 
IP values generally increase from left to right in 
any series but the increase is less than that of s 
block elements due to increase in nuclear charge is 
opposed by screening effect.
 
Ionization Enthalpy:  Zn > Fe > Co > Cu > Ni > 
Mn > Ti > Cr > V >Sc
2
Most Wanted
(4) Oxidation State
Transition elements exhibit variable oxidation st ate 
due to small energy difference of ns and (n – 1)d 
electrons.
 
Sc(+3) and Zn(+2) exhibit only one oxidation state
 
Common oxidation state is +2
 
3d series highest oxidation state is +7 (Mn)
 
In d-block series highest oxidation state is +8 (Os, Ru)
In carbonyl compound oxidation state of metals is 
zero due to synergic effects.
The common examples are [Ni(CO)
4
], [Fe(CO)
5
] in 
which nickel and iron are in zero oxidation state.
 
Their higher oxidation states are more stable in 
fluoride and oxides.
 
Higher oxidation states in oxides are normally more 
stable than fluorides due to capability of oxygen to 
form multiple bonds.
Some more stable oxidation states of d-block 
elements
Cu + 2 Mn + 2 Pt + 4 Ag + 1
Cu + 3 Sc + 3 Au + 3 Ni + 2
Common oxidation states
Ti (+ 4) V (+5) Cr (+3, +5) Mn (+2, +4, +7)
Fe(+2, +3) Co (+2, +3) Ni (+2) Pt(+2, +4)
In p-block lower oxidation states of heavier elements 
are more stable while in d-block heavier element, 
higher oxidation state are more stable.
(5) Electrode potentials and chemical reactivity
Trends in the M
2+
/M Standard electro potential
 
S.R.P of M
+2
/M values increases from left to right 
as IP values increases. (except Zn)
Cu cannot displace H
2
 from acids because it has 
highest S.R.P value which is +0.34 V .
 
Mn, Ni and Zn have more negative S.R.P values 
than expected because.
 
Reason: Mn & Zn have d
5
 & d
10
 stable electronic 
configuration Ni has highest hydration energy.
 (DH
Hyd
 Ni
+2
 = –2121 kJ/mole)
Trends in the M
3+
/M
2+
 Standard electro potential
 
32
0
M /M
E
++ in the 3d series are observed for some 
metals are
Co
+3
/Co
+2
 > Mn
+3
/Mn
+2
> Fe
+3
/Fe
+2 
> Ti
+3
/Ti
+2 
> 
Sc
+3
/Sc
+2
>V
+3
/V
+2
(6) Magnetic Property of Transition Metals
 
Paramagnetic substances contain unpaired electron 
spins or unpaired electrons.
 
Ex : K
3
[Fe(CN)
6
], Sc
2+
, Cr
3+
 etc
 
Diamagnetic substances exhibit decrease in weight 
in the presence of magnetic field.
 
Ex.: Ti
+4
, V
+5
 , Sc
3+
, Zn, Hg, Cd etc
 
Diamagnetic substances contain electron pairs with 
opposite spins.
 
Ferromagnetic substances are considered as a 
special case of paramagnetic substances.
 
Paramagnetism of substances (molecules, atoms or 
ions)is due to the spins of the unpaired electrons 
and also due to angular orbital momentum.
In terms of number of unpaired electrons (n), the 
magnetic moment is given by the formula.
 ( )
s
nn 2 µ= + BM
 Q. The magnetic moment of Ni
2+
 ion (atomic 
number of Ni = 28) in BM unit is:
a. 1.73 b. 4.81
c. 5.96 d. 2.84
 Ans. (d) Ni
28
 = [Ar] 3d
8
 , 4s
2
Ni
2+
 = [Ar] 3d
8 
? n = 2
n(n 2) 2(2 2) 2(4) 8 2.84BM µ= += += = =
 Q. The correct order of magnetic moments (spin 
only values in B.M.) among is
a. [Fe(CN)
6
]
4–
 > [MnCl
4
]
2–
 > [CoCl
4
]
2–
b. [MnCl
4
]
2–
 > [Fe(CN)
6
]
4–
 > [CoCl
4
]
2–
c. [MnCl
4
]
2–
 > [CoCl
4
]
2–
 > [Fe(CN)
6
]
4–
d. [Fe(CN)
6
]
4–
 > [CoCl
4
]
2–
 > [MnCl
4
]
2–
 Ans. (c) 
        
SCAN (Special Cases Asked in NEET)
3
The d & f-Block Elements
(7) Colours of Transition Metal Ions
Colour in transition metal ions is associated with d-d 
transition of unpaired electron from t
2g
 to e
g
 set of 
energies.
(8) Formation of complexes
The great tendency of transition metal ions to form 
complexes is due to : small size of the atoms and 
ions, high nuclear charge and availability of vacant 
d-orbitals of suitable energy to accept lone pairs of 
electrons donated by ligands.
(9) Catalytic properties of transition metals
Good catalysts due to the presence of free valencies 
and also variable oxidation states.
(10) Formation of Interstitial Compounds
 
From interstitial compounds: As they are able to 
entrap atoms of elements having small atomic size 
like H, C, N, B etc.
 
The general characteristic physical and chemical 
properties of these compounds are :
 ? High melting points which are higher than 
those of pure metals.
 ? Retain metallic conductivity i.e. of pure metals.
 ? Very hard and some borides have hardness as 
that of diamond.
 ? Chemically inert.
(11) Alloy Formation
Solid mixture of metals in a definate ratio (15% 
difference in metallic radius)
They are hard and having high melting point.
eg.,  Brass (Cu + Zn) 
        Bronze (Cu + Sn) etc.
Hg when mix with other metals form semisolid 
amalgam except Fe, Co, Ni, Li.
Potassium Dichromate (K
2
Cr
2
O
7
)
Properties
(a) Physical:
Fig.: Dichromate ion orange, red colour
K
2
Cr
2
O
7
 is preferred over Na
2
Cr
2
O
7
 as a primary 
standard in volumetric estimation because 
Na
2
Cr
2
O
7
 is hygroscopic in nature but K
2
Cr
2
O
7
 is 
not.
Key Note ?
(b) Chemical:
 ?
2 2 7 2 4 23 2
3
2K Cr O 2K CrO Cr O O
2
?
??? + +
  K
2
Cr
2
O
7
 + 2KOH ?? 2K
2
CrO
4
 + H
2
O
  Cr
2
O
2–
7
 + 2OH¯ ?? 2CrO
4
2–
 + H
2
O
Orange       Y ellow? (color change in 
     basic medium)
  2CrO
4
2–
 + 2H
+
 ?? Cr
2
O
7
2–
 + H
2
O
          
Yellow          Orange ? (color change in 
     acidic medium)
CrO
4
2–
 and Cr
2
O
7
2–
 exist in equilibrium and are 
interconvertable by altering the pH of solution.
2CrO
4
2–
 + 2H
+
 ? 2HCrO
4
–
 ? Cr
2
O
7
2–
 + H
2
O
 ? It acts as a powerful oxidising agent in acidic 
medium (dilute H
2
SO
4
)
 Cr
2
+6
 O
7
2–
 + 14H
+
 + 6e
–
 ?? 2Cr
3+
 + 7H
2
O.   
    (Eº = 1.33 V)
Reaction of Acidified potassium dichromate
K
2
Cr
2
O
7
 + 3Na
2
SO
3
 + 4H
2
SO
4
 
                      ?? Cr
2
 (SO
4
)
3
 + 3Na
2
SO
4
 + K
2
SO
4
K
2
Cr
2
O
7
 + 3SO
2
(g) + H
2
SO
4
 
                                           ?? Cr
2
 (SO
4
)
3
 + K
2
SO
4
 Q. The reaction of acidified potassium dichromate 
with Na
2
SO
3 
produces a compound that show 
green colour. Identify the compound.
a. Cr
2
 (SO
4
)
3  
b. K
2
SO
4
c. Cr
2
O
4
2– 
d. MnO
2
 
 Ans. (a) K
2
Cr
2
O
7
 + 3Na
2
SO
3
 + 4H
2
SO
4
 
                         ?? Cr
2
 (SO
4
)
3
 + 3Na
2
SO
4
 + K
2
SO
4
                                 green colour
SCAN (Special Cases Asked in NEET)
Potassium Permanganate (KMnO
4
)
Preparation
 
Commercially it is prepared by fusion of MnO
2
 
with KOH followed by electrolytic oxidation of 
manganate.
 MnO
4
2–
 (green) ?? MnO
4
–
 (purple) + e
–
Page 4


8
The d & f-Block 
Elements
Electronic Configurations/ (n–1) d
1–10 
ns
1–2
.
Exceptions: 1. Cr = 4s
1
 3d
5
       2. Cu = 4s
1
 3d
10
       3. Pd = 5s
0
4d
10
Transition Series
1
st
3d series Sc
21
 - Zn
30
 9 + 1 = 10
2
nd
4d series Y
39
 - Cd
48
 9 + 1 = 10
3
rd
5d series La
57
, Hf
72 
- Hg
80
 9 + 1 = 10
4
th
6d series Ac
89
, Unq
104
- Uub
112
 9 + 1 = 10
General Properties of Transition 
Element
 
The transition elements exhibit typical 
characteristic properties due to their small atomic 
sizes, large nuclear charges and the presence of 
unpaired d - electrons.
 
Enthalpy of atomization: V > Ti > Ni > Co > Fe > 
Cr > Cu > Sc > Mn > Zn
(1) Trends in M.P of transition elements(TE)
 
In any row the melting points of these metals rise 
to a maximum at d
5
 except for anomalous values 
of Mn and Tc and fall regularly as the atomic 
number increases. They have high enthalpies of 
atomization. The maxima at about the middle of 
each series indicate that one unpaired electron 
per d orbital is particularly favorable for strong 
interatomic interaction.
Number of valence electrons increase
?
strong bonding
?
higher enthalpy of atomisation
 ?
higher boiling point
?
higher standard electronic potential
?
More noble character
M.P./10 K
3
Hf
Ta
W
Re
Os
Ir
Pt
Nb
Mo
Ru
Tc
Zr
Ti
V
Cr
Rh
Fe
Mn
Co
Pd
Ni
Cu
Au
Ag
Atomic number
Trends in melting points of
transition elements
1
2
3
4
After chromium, the number of unpaired electrons 
goes on decreasing. Accordingly, the melting points 
decrease after middle (Cr) because of increasing 
pairing of electrons.
(2) Size of atoms and ions
 
The covalent radii of the elements decreases from 
left to right across a row in the transition series, 
until near the end when the size increases slightly.
 
Metallic radii: Sc > Ti > Mn = Zn > V > Cr > Cu>  
Co = Ni
(3) Ionization Energies of 3d Series
 
IP values generally increase from left to right in 
any series but the increase is less than that of s 
block elements due to increase in nuclear charge is 
opposed by screening effect.
 
Ionization Enthalpy:  Zn > Fe > Co > Cu > Ni > 
Mn > Ti > Cr > V >Sc
2
Most Wanted
(4) Oxidation State
Transition elements exhibit variable oxidation st ate 
due to small energy difference of ns and (n – 1)d 
electrons.
 
Sc(+3) and Zn(+2) exhibit only one oxidation state
 
Common oxidation state is +2
 
3d series highest oxidation state is +7 (Mn)
 
In d-block series highest oxidation state is +8 (Os, Ru)
In carbonyl compound oxidation state of metals is 
zero due to synergic effects.
The common examples are [Ni(CO)
4
], [Fe(CO)
5
] in 
which nickel and iron are in zero oxidation state.
 
Their higher oxidation states are more stable in 
fluoride and oxides.
 
Higher oxidation states in oxides are normally more 
stable than fluorides due to capability of oxygen to 
form multiple bonds.
Some more stable oxidation states of d-block 
elements
Cu + 2 Mn + 2 Pt + 4 Ag + 1
Cu + 3 Sc + 3 Au + 3 Ni + 2
Common oxidation states
Ti (+ 4) V (+5) Cr (+3, +5) Mn (+2, +4, +7)
Fe(+2, +3) Co (+2, +3) Ni (+2) Pt(+2, +4)
In p-block lower oxidation states of heavier elements 
are more stable while in d-block heavier element, 
higher oxidation state are more stable.
(5) Electrode potentials and chemical reactivity
Trends in the M
2+
/M Standard electro potential
 
S.R.P of M
+2
/M values increases from left to right 
as IP values increases. (except Zn)
Cu cannot displace H
2
 from acids because it has 
highest S.R.P value which is +0.34 V .
 
Mn, Ni and Zn have more negative S.R.P values 
than expected because.
 
Reason: Mn & Zn have d
5
 & d
10
 stable electronic 
configuration Ni has highest hydration energy.
 (DH
Hyd
 Ni
+2
 = –2121 kJ/mole)
Trends in the M
3+
/M
2+
 Standard electro potential
 
32
0
M /M
E
++ in the 3d series are observed for some 
metals are
Co
+3
/Co
+2
 > Mn
+3
/Mn
+2
> Fe
+3
/Fe
+2 
> Ti
+3
/Ti
+2 
> 
Sc
+3
/Sc
+2
>V
+3
/V
+2
(6) Magnetic Property of Transition Metals
 
Paramagnetic substances contain unpaired electron 
spins or unpaired electrons.
 
Ex : K
3
[Fe(CN)
6
], Sc
2+
, Cr
3+
 etc
 
Diamagnetic substances exhibit decrease in weight 
in the presence of magnetic field.
 
Ex.: Ti
+4
, V
+5
 , Sc
3+
, Zn, Hg, Cd etc
 
Diamagnetic substances contain electron pairs with 
opposite spins.
 
Ferromagnetic substances are considered as a 
special case of paramagnetic substances.
 
Paramagnetism of substances (molecules, atoms or 
ions)is due to the spins of the unpaired electrons 
and also due to angular orbital momentum.
In terms of number of unpaired electrons (n), the 
magnetic moment is given by the formula.
 ( )
s
nn 2 µ= + BM
 Q. The magnetic moment of Ni
2+
 ion (atomic 
number of Ni = 28) in BM unit is:
a. 1.73 b. 4.81
c. 5.96 d. 2.84
 Ans. (d) Ni
28
 = [Ar] 3d
8
 , 4s
2
Ni
2+
 = [Ar] 3d
8 
? n = 2
n(n 2) 2(2 2) 2(4) 8 2.84BM µ= += += = =
 Q. The correct order of magnetic moments (spin 
only values in B.M.) among is
a. [Fe(CN)
6
]
4–
 > [MnCl
4
]
2–
 > [CoCl
4
]
2–
b. [MnCl
4
]
2–
 > [Fe(CN)
6
]
4–
 > [CoCl
4
]
2–
c. [MnCl
4
]
2–
 > [CoCl
4
]
2–
 > [Fe(CN)
6
]
4–
d. [Fe(CN)
6
]
4–
 > [CoCl
4
]
2–
 > [MnCl
4
]
2–
 Ans. (c) 
        
SCAN (Special Cases Asked in NEET)
3
The d & f-Block Elements
(7) Colours of Transition Metal Ions
Colour in transition metal ions is associated with d-d 
transition of unpaired electron from t
2g
 to e
g
 set of 
energies.
(8) Formation of complexes
The great tendency of transition metal ions to form 
complexes is due to : small size of the atoms and 
ions, high nuclear charge and availability of vacant 
d-orbitals of suitable energy to accept lone pairs of 
electrons donated by ligands.
(9) Catalytic properties of transition metals
Good catalysts due to the presence of free valencies 
and also variable oxidation states.
(10) Formation of Interstitial Compounds
 
From interstitial compounds: As they are able to 
entrap atoms of elements having small atomic size 
like H, C, N, B etc.
 
The general characteristic physical and chemical 
properties of these compounds are :
 ? High melting points which are higher than 
those of pure metals.
 ? Retain metallic conductivity i.e. of pure metals.
 ? Very hard and some borides have hardness as 
that of diamond.
 ? Chemically inert.
(11) Alloy Formation
Solid mixture of metals in a definate ratio (15% 
difference in metallic radius)
They are hard and having high melting point.
eg.,  Brass (Cu + Zn) 
        Bronze (Cu + Sn) etc.
Hg when mix with other metals form semisolid 
amalgam except Fe, Co, Ni, Li.
Potassium Dichromate (K
2
Cr
2
O
7
)
Properties
(a) Physical:
Fig.: Dichromate ion orange, red colour
K
2
Cr
2
O
7
 is preferred over Na
2
Cr
2
O
7
 as a primary 
standard in volumetric estimation because 
Na
2
Cr
2
O
7
 is hygroscopic in nature but K
2
Cr
2
O
7
 is 
not.
Key Note ?
(b) Chemical:
 ?
2 2 7 2 4 23 2
3
2K Cr O 2K CrO Cr O O
2
?
??? + +
  K
2
Cr
2
O
7
 + 2KOH ?? 2K
2
CrO
4
 + H
2
O
  Cr
2
O
2–
7
 + 2OH¯ ?? 2CrO
4
2–
 + H
2
O
Orange       Y ellow? (color change in 
     basic medium)
  2CrO
4
2–
 + 2H
+
 ?? Cr
2
O
7
2–
 + H
2
O
          
Yellow          Orange ? (color change in 
     acidic medium)
CrO
4
2–
 and Cr
2
O
7
2–
 exist in equilibrium and are 
interconvertable by altering the pH of solution.
2CrO
4
2–
 + 2H
+
 ? 2HCrO
4
–
 ? Cr
2
O
7
2–
 + H
2
O
 ? It acts as a powerful oxidising agent in acidic 
medium (dilute H
2
SO
4
)
 Cr
2
+6
 O
7
2–
 + 14H
+
 + 6e
–
 ?? 2Cr
3+
 + 7H
2
O.   
    (Eº = 1.33 V)
Reaction of Acidified potassium dichromate
K
2
Cr
2
O
7
 + 3Na
2
SO
3
 + 4H
2
SO
4
 
                      ?? Cr
2
 (SO
4
)
3
 + 3Na
2
SO
4
 + K
2
SO
4
K
2
Cr
2
O
7
 + 3SO
2
(g) + H
2
SO
4
 
                                           ?? Cr
2
 (SO
4
)
3
 + K
2
SO
4
 Q. The reaction of acidified potassium dichromate 
with Na
2
SO
3 
produces a compound that show 
green colour. Identify the compound.
a. Cr
2
 (SO
4
)
3  
b. K
2
SO
4
c. Cr
2
O
4
2– 
d. MnO
2
 
 Ans. (a) K
2
Cr
2
O
7
 + 3Na
2
SO
3
 + 4H
2
SO
4
 
                         ?? Cr
2
 (SO
4
)
3
 + 3Na
2
SO
4
 + K
2
SO
4
                                 green colour
SCAN (Special Cases Asked in NEET)
Potassium Permanganate (KMnO
4
)
Preparation
 
Commercially it is prepared by fusion of MnO
2
 
with KOH followed by electrolytic oxidation of 
manganate.
 MnO
4
2–
 (green) ?? MnO
4
–
 (purple) + e
–
4
Most Wanted
 
In the lab
 2Mn
2+
 + 5S
2
O
8
2–
 + 8H
2
O ?? 2MnO
4
–
 + 10SO
4
2–
   
         +16H
+
Properties
(a) Physical: 
Tetrahedral manganate 
(green) ion
(Paramagnetic)
Terahedral permanganate 
(purple) ion  
(Diamagnetic)
MnO
4
2–
 & MnO
4
–
 contains one and zero 
unpaired electron respectively
 Q. Predict the magnetic nature of manganate and 
permanganate ion.
a. Paramagnetic, diamagnetic
b. Diamagnetic, Paramagnetic
c. Paramagnetic, Paramagnetic
d. Diamagnetic, Diamagnetic
Ans. (a) Manganate  (MnO
4
2–
) Paramanganate 
(MnO
4
–
)
The green manganate is paramagnetic with 
one unpaired electron but the permanganate 
is diamagnetic.
SCAN (Special Cases Asked in NEET)
(b) Chemical:
 (i) Effect of heating 
  2KMnO
4
 
751K
???? K
2
MnO
4
 + MnO
2
 + O
2
In alkaline & neutral medium:
 2KMnO
4
 + 2KOH ?? 2K
2
 MnO
4
 + H
2
O + [O]  
             (conc.)    manganate 
 If solution is dilute
 2K
2
MnO
4
 + 2H
2
O ?? 2MnO
2
 + 4KOH + 2[O]
     (Brown ppt)
 This type of behaviour is shown by KMnO
4
 itself 
in neutral medium
 3e
–
 + 2H
2
O + MnO
4
–
 ?? MnO
2
 + 4OH
–
 
 In alkaline or neutral medium KMnO
4
 shows 
oxidising properties.
In acidic medium (in presence of dilute H
2
SO
4
):
 
  MnO
4
–
 + 5Fe
2+
 + 8H
+
 ?? 5Fe
3+
 + Mn
2+
 + 4H
2
O
         Green         yellow
oxidised
2MnO
4
–
 + 5SO
2
 + 2H
2
O ?? 5SO
4
2–
 + 2Mn
2+
 + 4H
+
oxidised
The Inner Transition f-Block 
Elements
f-block
Lanthanides Actinides
Lanthanides
Electronic configuration - 4f
14
 5d
0-1
 6s
2
La   to   Lu
(57)          (71)
Properties
Atomic sizes
 
There is decrease in atomic and ionic radii from 
lanthanum to lutetium due to lanthanoid contraction. 
However, the shielding of one 4f electron by another 
is less than a d-electron by another with the increase 
in nuclear charge along the series.
The net result of the lanthanoid contraction is that 
the second and the third d series exhibit similar 
radii (e.g., Zr 160 pm, Hf 159 pm) and have very 
similar physical and chemical properties much 
more than that expected on the basis of usual 
family relationship.
 Q. The pair that is referred as ‘chemical twins’ is:
a. Ac, Cf b. Hf, Ta c. Tc, Re d. La, Ac
 Ans. (c) Tc & Re belongs to same group. The atomic 
radius of elements of second transition series is 
similar to that of third transition elements, due 
to poor shielding of f-orbitals.(MnO
4
–
)
The green manganate is paramagnetic with 
one unpaired electron but the permanganate 
is diamagnetic.
SCAN (Special Cases Asked in NEET)
Physical Properties
Density: Increases with increase in atomic number.
Electropositive Character: Highly electropositive 
due to their low Ionisation energy.
Ionisation Energy: Low ionisation energies, IE
1
 & IE
2
  are equal to calcium ionisation enthalpy
Page 5


8
The d & f-Block 
Elements
Electronic Configurations/ (n–1) d
1–10 
ns
1–2
.
Exceptions: 1. Cr = 4s
1
 3d
5
       2. Cu = 4s
1
 3d
10
       3. Pd = 5s
0
4d
10
Transition Series
1
st
3d series Sc
21
 - Zn
30
 9 + 1 = 10
2
nd
4d series Y
39
 - Cd
48
 9 + 1 = 10
3
rd
5d series La
57
, Hf
72 
- Hg
80
 9 + 1 = 10
4
th
6d series Ac
89
, Unq
104
- Uub
112
 9 + 1 = 10
General Properties of Transition 
Element
 
The transition elements exhibit typical 
characteristic properties due to their small atomic 
sizes, large nuclear charges and the presence of 
unpaired d - electrons.
 
Enthalpy of atomization: V > Ti > Ni > Co > Fe > 
Cr > Cu > Sc > Mn > Zn
(1) Trends in M.P of transition elements(TE)
 
In any row the melting points of these metals rise 
to a maximum at d
5
 except for anomalous values 
of Mn and Tc and fall regularly as the atomic 
number increases. They have high enthalpies of 
atomization. The maxima at about the middle of 
each series indicate that one unpaired electron 
per d orbital is particularly favorable for strong 
interatomic interaction.
Number of valence electrons increase
?
strong bonding
?
higher enthalpy of atomisation
 ?
higher boiling point
?
higher standard electronic potential
?
More noble character
M.P./10 K
3
Hf
Ta
W
Re
Os
Ir
Pt
Nb
Mo
Ru
Tc
Zr
Ti
V
Cr
Rh
Fe
Mn
Co
Pd
Ni
Cu
Au
Ag
Atomic number
Trends in melting points of
transition elements
1
2
3
4
After chromium, the number of unpaired electrons 
goes on decreasing. Accordingly, the melting points 
decrease after middle (Cr) because of increasing 
pairing of electrons.
(2) Size of atoms and ions
 
The covalent radii of the elements decreases from 
left to right across a row in the transition series, 
until near the end when the size increases slightly.
 
Metallic radii: Sc > Ti > Mn = Zn > V > Cr > Cu>  
Co = Ni
(3) Ionization Energies of 3d Series
 
IP values generally increase from left to right in 
any series but the increase is less than that of s 
block elements due to increase in nuclear charge is 
opposed by screening effect.
 
Ionization Enthalpy:  Zn > Fe > Co > Cu > Ni > 
Mn > Ti > Cr > V >Sc
2
Most Wanted
(4) Oxidation State
Transition elements exhibit variable oxidation st ate 
due to small energy difference of ns and (n – 1)d 
electrons.
 
Sc(+3) and Zn(+2) exhibit only one oxidation state
 
Common oxidation state is +2
 
3d series highest oxidation state is +7 (Mn)
 
In d-block series highest oxidation state is +8 (Os, Ru)
In carbonyl compound oxidation state of metals is 
zero due to synergic effects.
The common examples are [Ni(CO)
4
], [Fe(CO)
5
] in 
which nickel and iron are in zero oxidation state.
 
Their higher oxidation states are more stable in 
fluoride and oxides.
 
Higher oxidation states in oxides are normally more 
stable than fluorides due to capability of oxygen to 
form multiple bonds.
Some more stable oxidation states of d-block 
elements
Cu + 2 Mn + 2 Pt + 4 Ag + 1
Cu + 3 Sc + 3 Au + 3 Ni + 2
Common oxidation states
Ti (+ 4) V (+5) Cr (+3, +5) Mn (+2, +4, +7)
Fe(+2, +3) Co (+2, +3) Ni (+2) Pt(+2, +4)
In p-block lower oxidation states of heavier elements 
are more stable while in d-block heavier element, 
higher oxidation state are more stable.
(5) Electrode potentials and chemical reactivity
Trends in the M
2+
/M Standard electro potential
 
S.R.P of M
+2
/M values increases from left to right 
as IP values increases. (except Zn)
Cu cannot displace H
2
 from acids because it has 
highest S.R.P value which is +0.34 V .
 
Mn, Ni and Zn have more negative S.R.P values 
than expected because.
 
Reason: Mn & Zn have d
5
 & d
10
 stable electronic 
configuration Ni has highest hydration energy.
 (DH
Hyd
 Ni
+2
 = –2121 kJ/mole)
Trends in the M
3+
/M
2+
 Standard electro potential
 
32
0
M /M
E
++ in the 3d series are observed for some 
metals are
Co
+3
/Co
+2
 > Mn
+3
/Mn
+2
> Fe
+3
/Fe
+2 
> Ti
+3
/Ti
+2 
> 
Sc
+3
/Sc
+2
>V
+3
/V
+2
(6) Magnetic Property of Transition Metals
 
Paramagnetic substances contain unpaired electron 
spins or unpaired electrons.
 
Ex : K
3
[Fe(CN)
6
], Sc
2+
, Cr
3+
 etc
 
Diamagnetic substances exhibit decrease in weight 
in the presence of magnetic field.
 
Ex.: Ti
+4
, V
+5
 , Sc
3+
, Zn, Hg, Cd etc
 
Diamagnetic substances contain electron pairs with 
opposite spins.
 
Ferromagnetic substances are considered as a 
special case of paramagnetic substances.
 
Paramagnetism of substances (molecules, atoms or 
ions)is due to the spins of the unpaired electrons 
and also due to angular orbital momentum.
In terms of number of unpaired electrons (n), the 
magnetic moment is given by the formula.
 ( )
s
nn 2 µ= + BM
 Q. The magnetic moment of Ni
2+
 ion (atomic 
number of Ni = 28) in BM unit is:
a. 1.73 b. 4.81
c. 5.96 d. 2.84
 Ans. (d) Ni
28
 = [Ar] 3d
8
 , 4s
2
Ni
2+
 = [Ar] 3d
8 
? n = 2
n(n 2) 2(2 2) 2(4) 8 2.84BM µ= += += = =
 Q. The correct order of magnetic moments (spin 
only values in B.M.) among is
a. [Fe(CN)
6
]
4–
 > [MnCl
4
]
2–
 > [CoCl
4
]
2–
b. [MnCl
4
]
2–
 > [Fe(CN)
6
]
4–
 > [CoCl
4
]
2–
c. [MnCl
4
]
2–
 > [CoCl
4
]
2–
 > [Fe(CN)
6
]
4–
d. [Fe(CN)
6
]
4–
 > [CoCl
4
]
2–
 > [MnCl
4
]
2–
 Ans. (c) 
        
SCAN (Special Cases Asked in NEET)
3
The d & f-Block Elements
(7) Colours of Transition Metal Ions
Colour in transition metal ions is associated with d-d 
transition of unpaired electron from t
2g
 to e
g
 set of 
energies.
(8) Formation of complexes
The great tendency of transition metal ions to form 
complexes is due to : small size of the atoms and 
ions, high nuclear charge and availability of vacant 
d-orbitals of suitable energy to accept lone pairs of 
electrons donated by ligands.
(9) Catalytic properties of transition metals
Good catalysts due to the presence of free valencies 
and also variable oxidation states.
(10) Formation of Interstitial Compounds
 
From interstitial compounds: As they are able to 
entrap atoms of elements having small atomic size 
like H, C, N, B etc.
 
The general characteristic physical and chemical 
properties of these compounds are :
 ? High melting points which are higher than 
those of pure metals.
 ? Retain metallic conductivity i.e. of pure metals.
 ? Very hard and some borides have hardness as 
that of diamond.
 ? Chemically inert.
(11) Alloy Formation
Solid mixture of metals in a definate ratio (15% 
difference in metallic radius)
They are hard and having high melting point.
eg.,  Brass (Cu + Zn) 
        Bronze (Cu + Sn) etc.
Hg when mix with other metals form semisolid 
amalgam except Fe, Co, Ni, Li.
Potassium Dichromate (K
2
Cr
2
O
7
)
Properties
(a) Physical:
Fig.: Dichromate ion orange, red colour
K
2
Cr
2
O
7
 is preferred over Na
2
Cr
2
O
7
 as a primary 
standard in volumetric estimation because 
Na
2
Cr
2
O
7
 is hygroscopic in nature but K
2
Cr
2
O
7
 is 
not.
Key Note ?
(b) Chemical:
 ?
2 2 7 2 4 23 2
3
2K Cr O 2K CrO Cr O O
2
?
??? + +
  K
2
Cr
2
O
7
 + 2KOH ?? 2K
2
CrO
4
 + H
2
O
  Cr
2
O
2–
7
 + 2OH¯ ?? 2CrO
4
2–
 + H
2
O
Orange       Y ellow? (color change in 
     basic medium)
  2CrO
4
2–
 + 2H
+
 ?? Cr
2
O
7
2–
 + H
2
O
          
Yellow          Orange ? (color change in 
     acidic medium)
CrO
4
2–
 and Cr
2
O
7
2–
 exist in equilibrium and are 
interconvertable by altering the pH of solution.
2CrO
4
2–
 + 2H
+
 ? 2HCrO
4
–
 ? Cr
2
O
7
2–
 + H
2
O
 ? It acts as a powerful oxidising agent in acidic 
medium (dilute H
2
SO
4
)
 Cr
2
+6
 O
7
2–
 + 14H
+
 + 6e
–
 ?? 2Cr
3+
 + 7H
2
O.   
    (Eº = 1.33 V)
Reaction of Acidified potassium dichromate
K
2
Cr
2
O
7
 + 3Na
2
SO
3
 + 4H
2
SO
4
 
                      ?? Cr
2
 (SO
4
)
3
 + 3Na
2
SO
4
 + K
2
SO
4
K
2
Cr
2
O
7
 + 3SO
2
(g) + H
2
SO
4
 
                                           ?? Cr
2
 (SO
4
)
3
 + K
2
SO
4
 Q. The reaction of acidified potassium dichromate 
with Na
2
SO
3 
produces a compound that show 
green colour. Identify the compound.
a. Cr
2
 (SO
4
)
3  
b. K
2
SO
4
c. Cr
2
O
4
2– 
d. MnO
2
 
 Ans. (a) K
2
Cr
2
O
7
 + 3Na
2
SO
3
 + 4H
2
SO
4
 
                         ?? Cr
2
 (SO
4
)
3
 + 3Na
2
SO
4
 + K
2
SO
4
                                 green colour
SCAN (Special Cases Asked in NEET)
Potassium Permanganate (KMnO
4
)
Preparation
 
Commercially it is prepared by fusion of MnO
2
 
with KOH followed by electrolytic oxidation of 
manganate.
 MnO
4
2–
 (green) ?? MnO
4
–
 (purple) + e
–
4
Most Wanted
 
In the lab
 2Mn
2+
 + 5S
2
O
8
2–
 + 8H
2
O ?? 2MnO
4
–
 + 10SO
4
2–
   
         +16H
+
Properties
(a) Physical: 
Tetrahedral manganate 
(green) ion
(Paramagnetic)
Terahedral permanganate 
(purple) ion  
(Diamagnetic)
MnO
4
2–
 & MnO
4
–
 contains one and zero 
unpaired electron respectively
 Q. Predict the magnetic nature of manganate and 
permanganate ion.
a. Paramagnetic, diamagnetic
b. Diamagnetic, Paramagnetic
c. Paramagnetic, Paramagnetic
d. Diamagnetic, Diamagnetic
Ans. (a) Manganate  (MnO
4
2–
) Paramanganate 
(MnO
4
–
)
The green manganate is paramagnetic with 
one unpaired electron but the permanganate 
is diamagnetic.
SCAN (Special Cases Asked in NEET)
(b) Chemical:
 (i) Effect of heating 
  2KMnO
4
 
751K
???? K
2
MnO
4
 + MnO
2
 + O
2
In alkaline & neutral medium:
 2KMnO
4
 + 2KOH ?? 2K
2
 MnO
4
 + H
2
O + [O]  
             (conc.)    manganate 
 If solution is dilute
 2K
2
MnO
4
 + 2H
2
O ?? 2MnO
2
 + 4KOH + 2[O]
     (Brown ppt)
 This type of behaviour is shown by KMnO
4
 itself 
in neutral medium
 3e
–
 + 2H
2
O + MnO
4
–
 ?? MnO
2
 + 4OH
–
 
 In alkaline or neutral medium KMnO
4
 shows 
oxidising properties.
In acidic medium (in presence of dilute H
2
SO
4
):
 
  MnO
4
–
 + 5Fe
2+
 + 8H
+
 ?? 5Fe
3+
 + Mn
2+
 + 4H
2
O
         Green         yellow
oxidised
2MnO
4
–
 + 5SO
2
 + 2H
2
O ?? 5SO
4
2–
 + 2Mn
2+
 + 4H
+
oxidised
The Inner Transition f-Block 
Elements
f-block
Lanthanides Actinides
Lanthanides
Electronic configuration - 4f
14
 5d
0-1
 6s
2
La   to   Lu
(57)          (71)
Properties
Atomic sizes
 
There is decrease in atomic and ionic radii from 
lanthanum to lutetium due to lanthanoid contraction. 
However, the shielding of one 4f electron by another 
is less than a d-electron by another with the increase 
in nuclear charge along the series.
The net result of the lanthanoid contraction is that 
the second and the third d series exhibit similar 
radii (e.g., Zr 160 pm, Hf 159 pm) and have very 
similar physical and chemical properties much 
more than that expected on the basis of usual 
family relationship.
 Q. The pair that is referred as ‘chemical twins’ is:
a. Ac, Cf b. Hf, Ta c. Tc, Re d. La, Ac
 Ans. (c) Tc & Re belongs to same group. The atomic 
radius of elements of second transition series is 
similar to that of third transition elements, due 
to poor shielding of f-orbitals.(MnO
4
–
)
The green manganate is paramagnetic with 
one unpaired electron but the permanganate 
is diamagnetic.
SCAN (Special Cases Asked in NEET)
Physical Properties
Density: Increases with increase in atomic number.
Electropositive Character: Highly electropositive 
due to their low Ionisation energy.
Ionisation Energy: Low ionisation energies, IE
1
 & IE
2
  are equal to calcium ionisation enthalpy
5
The d & f-Block Elements
 
(f
0
)La
(f
7
)Gd
(f
14
)Lu
Low IE
3
 
Magnetic Behaviour
M
3+
 ions are 
paramagnetic
Diamagnetic
La
3+
, Ce
+4
 
f
0
Yb
2+
, Lu
3+
 
f
14
Ions
Colour
 
The colour is due to f-f transitions since they have 
partly filled f-orbitals.
Radioactivity
 
All Lanthanides except promethium and samarium 
are non-radioactive
Oxidation States
 
Common oxidation state + 3.
 
+3 oxidations state stable in La, Gd and Lu.
 
+3 oxidation state in Lanthanum, Gadolinium and 
Lutetium are especially stable because +3 ions of 
these elements have an empty (f
0
), a halffilled [f
7
] 
and completely filled (f
14
)] configurations.
 
Al though the formation of Eu
2+
 is favoured by the 
extra stability of its f
7
 configurations, but Eu
2+
 is 
a strong reducing agent and changes to Eu
3+
 in its 
reactions. Samarium (Sm) also shows +2 and +3 
oxidation states.
The E° Value for Ce
4+
/Ce
3+
 is +1.74 V which 
suggests that it can oxidise water. However, the 
reaction rate is very slow and hence Ce(IV) is a 
good analytical reagent.
The formation of Ce
IV
 is favoured by its noble 
gas configuration.
 Q. Although +3 is the characteristic oxidation 
state for lanthanoids but cerium also shows +4 
oxidation state because:
a. It has variable ionisation enthalpy
b. It has a tendency to attain noble gas 
configuration
c. It has a tendency to attain f 
0
 configuration
d. It resembles Pb
4+
SCAN (Special Cases Asked in NEET)
 Ans. (b,c) Electronic configuration of 
[ ]
2 02
58
54 4 5 6 . = Ce Xe f d s
 
Therefore, electronic configuration of 
[ ]
40
54
4.
+
= Ce Xe f
Thus, it has a tendency to attain noble gas 
configuration and attain f 
0
 configuration.
Chemical Reactivity of Lanthanides
 
Earlier members of the series are quite reactive 
similar to calcium but, with increasing atomic 
number, they behave more like Al.
 
Size of M
+3
 ion ? the covalent character in M-OH 
bond and their basic strength in their hydroxides 
? gradually from La(OH)
3
 to Lu(OH)
3
 due to 
Lanthanide contraction
Fig.: Chemical reactions of the lanthanoids
Actinoids
 
General electronic configuration ? 5f
1-4 
6d
0-1 
7s
2
 
Ac
89
 to Law
(103)
 
Properties
Atomic Size
Decrease in size of M
3+
 across series due to actinoid 
contraction (poor shielding by 5f electron)
Oxidation States
Large number of O.S due to comparable energy of 
5f, 6d and 7s energy level.
 
Common +3 O.S 
 
Also exhibit +4, +5, +6, +7 O.S
 
After uranium ? elements knows as transuranic 
element
Read More
Offer running on EduRev: Apply code STAYHOME200 to get INR 200 off on our premium plan EduRev Infinity!

Content Category

Related Searches

ppt

,

D and F block NOTES MBBS Notes | EduRev

,

mock tests for examination

,

Previous Year Questions with Solutions

,

past year papers

,

practice quizzes

,

shortcuts and tricks

,

Semester Notes

,

Viva Questions

,

MCQs

,

Objective type Questions

,

Summary

,

D and F block NOTES MBBS Notes | EduRev

,

video lectures

,

Important questions

,

study material

,

Extra Questions

,

Exam

,

Sample Paper

,

D and F block NOTES MBBS Notes | EduRev

,

Free

,

pdf

;