Flashcards for JEE Chemistry - Coordination Compounds Class 12

 Page 1


Coordination Compounds
Flash cards
Page 2


Coordination Compounds
Flash cards
Different types of salt are formed due to addition of molecular compounds.
1. Double salts: Double salts are those molecular compounds which exists only in 
crystal lattice but lose their identity in solution.
e.g., KCl. MgCl
2
.6H
2
O ? K
+
+ Mg
+2
+ 3Cl
–
+ 6H
2
O.
Double salts when dissolved in water ionise.
Page 3


Coordination Compounds
Flash cards
Different types of salt are formed due to addition of molecular compounds.
1. Double salts: Double salts are those molecular compounds which exists only in 
crystal lattice but lose their identity in solution.
e.g., KCl. MgCl
2
.6H
2
O ? K
+
+ Mg
+2
+ 3Cl
–
+ 6H
2
O.
Double salts when dissolved in water ionise.
2. Complex salts: Complex salts are those molecular compounds which retain 
their identity in solid / crystal lattice as well as in the solution.
e.g., Potassium ferrocyanide is a complex compound which is formed by adding 
KCN to a saturated solution of ferrous cyanide
4KCN + Fe(CN)
2
? K
4
[Fe(CN)
6
]
K
4
[Fe(CN)
6
] is dissolved in water, the resulting solution does not give positive tests 
for ferrous or cyanide ions but we get a positive test for [Fe(CN)
6
]
4 –
.
Page 4


Coordination Compounds
Flash cards
Different types of salt are formed due to addition of molecular compounds.
1. Double salts: Double salts are those molecular compounds which exists only in 
crystal lattice but lose their identity in solution.
e.g., KCl. MgCl
2
.6H
2
O ? K
+
+ Mg
+2
+ 3Cl
–
+ 6H
2
O.
Double salts when dissolved in water ionise.
2. Complex salts: Complex salts are those molecular compounds which retain 
their identity in solid / crystal lattice as well as in the solution.
e.g., Potassium ferrocyanide is a complex compound which is formed by adding 
KCN to a saturated solution of ferrous cyanide
4KCN + Fe(CN)
2
? K
4
[Fe(CN)
6
]
K
4
[Fe(CN)
6
] is dissolved in water, the resulting solution does not give positive tests 
for ferrous or cyanide ions but we get a positive test for [Fe(CN)
6
]
4 –
.
CO-ORDINATION COMPOUNDS (Continued)
Coordination compound may be defined as a compound that results from the 
combination of apparently saturated molecules of different species and retain its 
identity in the solids as well as in dissolved state.
The formation of a coordination compound involves two components.
1. An acceptor: Which can accept a pair of electrons from the donor. The acceptor 
is usually a metal with vacant orbitals available to accept a pair of electrons from 
one or more neutral molecules or anions. In [Fe(CN)
6
]
4 –
, Fe
++
ion is an acceptor, 
which is also called as central metal ion, which acts as Lewis acid.
Page 5


Coordination Compounds
Flash cards
Different types of salt are formed due to addition of molecular compounds.
1. Double salts: Double salts are those molecular compounds which exists only in 
crystal lattice but lose their identity in solution.
e.g., KCl. MgCl
2
.6H
2
O ? K
+
+ Mg
+2
+ 3Cl
–
+ 6H
2
O.
Double salts when dissolved in water ionise.
2. Complex salts: Complex salts are those molecular compounds which retain 
their identity in solid / crystal lattice as well as in the solution.
e.g., Potassium ferrocyanide is a complex compound which is formed by adding 
KCN to a saturated solution of ferrous cyanide
4KCN + Fe(CN)
2
? K
4
[Fe(CN)
6
]
K
4
[Fe(CN)
6
] is dissolved in water, the resulting solution does not give positive tests 
for ferrous or cyanide ions but we get a positive test for [Fe(CN)
6
]
4 –
.
CO-ORDINATION COMPOUNDS (Continued)
Coordination compound may be defined as a compound that results from the 
combination of apparently saturated molecules of different species and retain its 
identity in the solids as well as in dissolved state.
The formation of a coordination compound involves two components.
1. An acceptor: Which can accept a pair of electrons from the donor. The acceptor 
is usually a metal with vacant orbitals available to accept a pair of electrons from 
one or more neutral molecules or anions. In [Fe(CN)
6
]
4 –
, Fe
++
ion is an acceptor, 
which is also called as central metal ion, which acts as Lewis acid.
CO-ORDINATION COMPOUNDS (Continued)
2. A donor : An atom or a molecule which can donate a pair of electrons is a donor. 
Such donor atoms or molecules are electron rich and are called ligands, which act as 
Lewis bases.
Ligands may be neutral (NH
3
, H
2
O, C
6
H
5
N) or negatively charged species (:CN
–
,Cl
–
, 
Br
–
) or positively charged
Ligand is said to be unidentate if it has only one pair of electrons that it can donate 
e.g., NH
3
Ligand is said to be bidentate if it can bond from two positions