Coordination Compound Solved Examples | Chemistry for JEE Main & Advanced PDF Download

 Page 1


Solved Examples on Co-ordination 
Compounds 
JEE Mains 
Q1. The reaction between yttrium metal ?? and dilute hydrochloric acid produces 
?? ?? ( ?? ) and ?? ?? +
 ions. The molar ratio of yttrium used to hydrogen produced is 
(a) ?? : ?? 
(b) ?? : ?? 
(c) ?? : ?? 
(d) ?? : ?? 
Ans. (d) 
2Y
2 mol
+ 6HCl ? 2 Y Cl
3
+ 3 H
2
3 mol
 
???? . [ ???? ( ?? ?? ?? )
?? ]
?? +
 and [ ???? ( ???? )
?? ]
?? -
 differ in 
(a) geometry, magnetic moment 
(b) magnetic moment, colour 
(c) geometry, hybridization 
(d) hybridization, number of unpaired electrons 
Ans. (b) 
Q3. An aqueous solution containing 0.02 mole of [ ???? ( ????
?? )
?? ????
?? ] ???? and 0.02 mole 
of [ ???? ( ????
?? )
?? ???? ] ????
?? was prepared and its volume was made upto 2 litres. It was 
divided into two equal parts. 
?? st 
 part + excess ?? ?? ???? ?? ? [ ?? ] 
?? nd 
 part + excess ???????? ?? ? [ ?? ]. No. of moles of [ ?? ] and [ ?? ] are respectively 
(a) 0.01 and 0.01 
(b) 0.02 and 0.01 
(c) 0.01 and 0.02 
(d) 0.02 and 0.02 
Ans. (a) 
 Concentration =
 moles 
 volume 
=
. 02
2
= . 01 
Q4. In ???? ( ???? )
?? , the ???? - ?? bond possesses. 
(a) ?? character only 
(b) ionic character 
(c) both ?? and ?? character 
(d) ?? - character only 
Ans. (c) 
In metal carbonyl organometallic compounds the bond between metal atom and carbon 
monoxide ligand has both ?? and ?? characters. 
 
 
Page 2


Solved Examples on Co-ordination 
Compounds 
JEE Mains 
Q1. The reaction between yttrium metal ?? and dilute hydrochloric acid produces 
?? ?? ( ?? ) and ?? ?? +
 ions. The molar ratio of yttrium used to hydrogen produced is 
(a) ?? : ?? 
(b) ?? : ?? 
(c) ?? : ?? 
(d) ?? : ?? 
Ans. (d) 
2Y
2 mol
+ 6HCl ? 2 Y Cl
3
+ 3 H
2
3 mol
 
???? . [ ???? ( ?? ?? ?? )
?? ]
?? +
 and [ ???? ( ???? )
?? ]
?? -
 differ in 
(a) geometry, magnetic moment 
(b) magnetic moment, colour 
(c) geometry, hybridization 
(d) hybridization, number of unpaired electrons 
Ans. (b) 
Q3. An aqueous solution containing 0.02 mole of [ ???? ( ????
?? )
?? ????
?? ] ???? and 0.02 mole 
of [ ???? ( ????
?? )
?? ???? ] ????
?? was prepared and its volume was made upto 2 litres. It was 
divided into two equal parts. 
?? st 
 part + excess ?? ?? ???? ?? ? [ ?? ] 
?? nd 
 part + excess ???????? ?? ? [ ?? ]. No. of moles of [ ?? ] and [ ?? ] are respectively 
(a) 0.01 and 0.01 
(b) 0.02 and 0.01 
(c) 0.01 and 0.02 
(d) 0.02 and 0.02 
Ans. (a) 
 Concentration =
 moles 
 volume 
=
. 02
2
= . 01 
Q4. In ???? ( ???? )
?? , the ???? - ?? bond possesses. 
(a) ?? character only 
(b) ionic character 
(c) both ?? and ?? character 
(d) ?? - character only 
Ans. (c) 
In metal carbonyl organometallic compounds the bond between metal atom and carbon 
monoxide ligand has both ?? and ?? characters. 
 
 
Q5. Which of the following statements is not correct? 
(a) ?? ?? ?? ?? ?? is used as a catalyst in converting acetylene to acetaldehyde. 
(b) ?? ???? ?? ?? . ?? ?? ?? ?? on strong heating gives ?? ???? with the liberation of ????
?? and ?? ?? . 
(c) ?? ???? ?? ?? . ?? ?? ?? ?? on heating at ?????? ?? gives ?? ???? ?? ?? · ?? ?? ?? ?? . 
(d) On sublimation, black variety of ?????? changes to red variety. 
Ans. (c) 
Z n S O
4
. 7 H
2
O ?
?
?
Z n S O
4
· H
2
O ?
?
?
Z n S O
4
. 
???? . ????
?? ( ???? )
?? is diamagnetic. Which of the following reasons is correct? 
(a) Presence of one ???? as bridge group. 
(b) Presence of monodentate ligand. 
(c) Metal-metal ( ???? - ???? ) bond in molecule. 
(d) Resonance hybridization of ???? . 
Ans. (c) 
Q7. Amongst the following complexes, select the one having highest magnetic 
dipole moment. 
(a) [ ???? ( ?? ?? ?? )
?? ]
?? +
 
(b) [ ???? ( ?? ?? ?? )
?? ]
?? +
 
(c) [ ???? ( ?? ?? ?? )
?? ]
?? +
 
(d) [ ???? ( ?? ?? ?? )
?? ]
?? +
 
Ans. (b) 
Because Fe
2 +
 has four unpaired electrons. 
Q8. The co-ordination number and oxidation state of ???? in ?? ?? [ ???? ( ?? ?? ?? ?? )
?? ] are 
respectively 
(a) 6 and +3 
(b) 3 and 0 
(c) 4 and +2 
(d) 3 and +3 
Ans. (a) 
Co-ordination number of Cr
3 +
 ion is six because chromium ion is surrounded by three 
bidentate ligands. 
For oxidation state of central metal ion 
3 + ?? - 6 = 0 
[where, ?? is the oxidation state of central metal ion] 
Q9. Hybridization of ???? in ?? ?? [ ???? ( ???? )
?? ] is 
(a) ????
?? 
(b) ?? ?? ????
?? 
(c) ????
?? ? ?? ?? 
(d) ?? ?? ?? ?? 
Ans. (b) 
In the given complex of Fe
3 +
, as the co-ordination number is ' 6 ', there are two possibilities. 
It can be d
2
sp
3
 or sp
3
 d
2
. But the ligand attached with central metal ion, Fe
3 +
, is strong field 
ligand so it willpromate inner orbital complex, ?? 2
?? 3
. 
Q10. Transition metal compounds are usually coloured. This is due to the 
electronic transition 
(a) from ?? orbital to s-orbital 
Page 3


Solved Examples on Co-ordination 
Compounds 
JEE Mains 
Q1. The reaction between yttrium metal ?? and dilute hydrochloric acid produces 
?? ?? ( ?? ) and ?? ?? +
 ions. The molar ratio of yttrium used to hydrogen produced is 
(a) ?? : ?? 
(b) ?? : ?? 
(c) ?? : ?? 
(d) ?? : ?? 
Ans. (d) 
2Y
2 mol
+ 6HCl ? 2 Y Cl
3
+ 3 H
2
3 mol
 
???? . [ ???? ( ?? ?? ?? )
?? ]
?? +
 and [ ???? ( ???? )
?? ]
?? -
 differ in 
(a) geometry, magnetic moment 
(b) magnetic moment, colour 
(c) geometry, hybridization 
(d) hybridization, number of unpaired electrons 
Ans. (b) 
Q3. An aqueous solution containing 0.02 mole of [ ???? ( ????
?? )
?? ????
?? ] ???? and 0.02 mole 
of [ ???? ( ????
?? )
?? ???? ] ????
?? was prepared and its volume was made upto 2 litres. It was 
divided into two equal parts. 
?? st 
 part + excess ?? ?? ???? ?? ? [ ?? ] 
?? nd 
 part + excess ???????? ?? ? [ ?? ]. No. of moles of [ ?? ] and [ ?? ] are respectively 
(a) 0.01 and 0.01 
(b) 0.02 and 0.01 
(c) 0.01 and 0.02 
(d) 0.02 and 0.02 
Ans. (a) 
 Concentration =
 moles 
 volume 
=
. 02
2
= . 01 
Q4. In ???? ( ???? )
?? , the ???? - ?? bond possesses. 
(a) ?? character only 
(b) ionic character 
(c) both ?? and ?? character 
(d) ?? - character only 
Ans. (c) 
In metal carbonyl organometallic compounds the bond between metal atom and carbon 
monoxide ligand has both ?? and ?? characters. 
 
 
Q5. Which of the following statements is not correct? 
(a) ?? ?? ?? ?? ?? is used as a catalyst in converting acetylene to acetaldehyde. 
(b) ?? ???? ?? ?? . ?? ?? ?? ?? on strong heating gives ?? ???? with the liberation of ????
?? and ?? ?? . 
(c) ?? ???? ?? ?? . ?? ?? ?? ?? on heating at ?????? ?? gives ?? ???? ?? ?? · ?? ?? ?? ?? . 
(d) On sublimation, black variety of ?????? changes to red variety. 
Ans. (c) 
Z n S O
4
. 7 H
2
O ?
?
?
Z n S O
4
· H
2
O ?
?
?
Z n S O
4
. 
???? . ????
?? ( ???? )
?? is diamagnetic. Which of the following reasons is correct? 
(a) Presence of one ???? as bridge group. 
(b) Presence of monodentate ligand. 
(c) Metal-metal ( ???? - ???? ) bond in molecule. 
(d) Resonance hybridization of ???? . 
Ans. (c) 
Q7. Amongst the following complexes, select the one having highest magnetic 
dipole moment. 
(a) [ ???? ( ?? ?? ?? )
?? ]
?? +
 
(b) [ ???? ( ?? ?? ?? )
?? ]
?? +
 
(c) [ ???? ( ?? ?? ?? )
?? ]
?? +
 
(d) [ ???? ( ?? ?? ?? )
?? ]
?? +
 
Ans. (b) 
Because Fe
2 +
 has four unpaired electrons. 
Q8. The co-ordination number and oxidation state of ???? in ?? ?? [ ???? ( ?? ?? ?? ?? )
?? ] are 
respectively 
(a) 6 and +3 
(b) 3 and 0 
(c) 4 and +2 
(d) 3 and +3 
Ans. (a) 
Co-ordination number of Cr
3 +
 ion is six because chromium ion is surrounded by three 
bidentate ligands. 
For oxidation state of central metal ion 
3 + ?? - 6 = 0 
[where, ?? is the oxidation state of central metal ion] 
Q9. Hybridization of ???? in ?? ?? [ ???? ( ???? )
?? ] is 
(a) ????
?? 
(b) ?? ?? ????
?? 
(c) ????
?? ? ?? ?? 
(d) ?? ?? ?? ?? 
Ans. (b) 
In the given complex of Fe
3 +
, as the co-ordination number is ' 6 ', there are two possibilities. 
It can be d
2
sp
3
 or sp
3
 d
2
. But the ligand attached with central metal ion, Fe
3 +
, is strong field 
ligand so it willpromate inner orbital complex, ?? 2
?? 3
. 
Q10. Transition metal compounds are usually coloured. This is due to the 
electronic transition 
(a) from ?? orbital to s-orbital 
(b) from d orbital to s-orbitals 
(c) from d orbital to p-orbital 
(d) within the d-orbitals 
Ans.  (d) 
Many ionic and covalent compounds of transition elements are coloured and this colouring 
property is due to d - d electronic excitation. The colour of the compound is complimentary 
to the colour absorbed. 
Q11. A compound has an empirical formula ???????? ?? . ?? ????
?? . When an aqueous 
solution of this compound is mixed with excess of silver nitrate, 2 moles of ?? ?? ???? 
precipitates per mole of the compound. On reaction with excess of ?? ???? , no ????
?? +
is 
detected. Hence the compound is 
(a) [ ???? ( ????
?? )
?? ????
?? ] ???? 
(b) [ ???? ( ????
?? )
?? ???? ] ????
?? 
(c) [ ???? ( ????
?? )
?? ????
?? ] 
(d) [ ???? ( ????
?? )
?? ????
?? ] ???? . ????
?? 
Ans. (b) As the moles of A g Cl precipitated is 2 and no NH
4
+
is detected on reaction with excess 
of HCl, so the compound would be [ Co ( NH
3
)
5
Cl ] Cl
2
. 
?  
Q12. Which of the given statements is not true for the following reaction? 
[ ???? ( ?? ?? ?? )
?? ]
?? +
+ ?? ????
?? ? [ ???? ( ????
?? )
?? ]
?? +
+ ?? ?? ?? ?? 
(a) It is a ligand-substitution reaction. 
(b) ????
?? is a relatively strong field ligand while ?? ?? ?? is a weak field ligand. 
(c) During the reaction, there is a change in colour from light blue to dark blue. 
(d) [ ???? ( ????
?? )
?? ]
?? +
 has a tetrahedral structure and is paramagnetic. 
Ans: (d) 
For ?
29
Cu, outermost shell has electronic configuration of 3 d
10
4 s
1
. 
? ? Electronic configuration of Cu
2 +
= 3 d
9
4 s
°
 
? 
But due to strong field ligand ( NH
3
), unpaired electron of 3 d
9
 jumps to 4 p. Hence, 
? ? Hybridisation of Cu
2 +
 in [ Cu ( NH
3
)
4
]
2 +
 is ds p
2
 and it gives the square planar geometry. 
 
Q13. Which of the following statement is incorrect? 
(a) Most four-coordinated complexes of ????
?? +
 ions are square planar rather than 
tetrahedral. 
(b) The [ ???? ( ?? ?? ?? )
?? ]
?? +
 ion is more paramagnetic than the [ ???? ( ???? )
?? ]
?? -
 ion. 
(c) Square planar complexes are more stable than octahedral complexes. 
(d) The [ ???? ( ???? )
?? ]
?? -
 ion is paramagnetic but [ ???? ( ???? )
?? ]
?? -
 ion is diamagnetic. 
Ans: ( d ) [ Fe ( CN )
6
]
4 -
 has Fe
2 +
 and have no unpaired electron, so it is diamagnetic and 
[ Fe ( CN )
6
]
3 -
 has Fe
3 +
 and having one unpaired electron, so it is paramagnetic. 
 
Q14.  Which of the following compound is not having synergic bonding? 
(A) ???? ( ???? )
?? 
(B) [ ???? ( ???? )
?? ]
?? -
 
(C) [ ???? ( ?? - ?? ?? ?? ?? )
?? ] 
(D) [ ?????? ?? ]
?? -
 
Page 4


Solved Examples on Co-ordination 
Compounds 
JEE Mains 
Q1. The reaction between yttrium metal ?? and dilute hydrochloric acid produces 
?? ?? ( ?? ) and ?? ?? +
 ions. The molar ratio of yttrium used to hydrogen produced is 
(a) ?? : ?? 
(b) ?? : ?? 
(c) ?? : ?? 
(d) ?? : ?? 
Ans. (d) 
2Y
2 mol
+ 6HCl ? 2 Y Cl
3
+ 3 H
2
3 mol
 
???? . [ ???? ( ?? ?? ?? )
?? ]
?? +
 and [ ???? ( ???? )
?? ]
?? -
 differ in 
(a) geometry, magnetic moment 
(b) magnetic moment, colour 
(c) geometry, hybridization 
(d) hybridization, number of unpaired electrons 
Ans. (b) 
Q3. An aqueous solution containing 0.02 mole of [ ???? ( ????
?? )
?? ????
?? ] ???? and 0.02 mole 
of [ ???? ( ????
?? )
?? ???? ] ????
?? was prepared and its volume was made upto 2 litres. It was 
divided into two equal parts. 
?? st 
 part + excess ?? ?? ???? ?? ? [ ?? ] 
?? nd 
 part + excess ???????? ?? ? [ ?? ]. No. of moles of [ ?? ] and [ ?? ] are respectively 
(a) 0.01 and 0.01 
(b) 0.02 and 0.01 
(c) 0.01 and 0.02 
(d) 0.02 and 0.02 
Ans. (a) 
 Concentration =
 moles 
 volume 
=
. 02
2
= . 01 
Q4. In ???? ( ???? )
?? , the ???? - ?? bond possesses. 
(a) ?? character only 
(b) ionic character 
(c) both ?? and ?? character 
(d) ?? - character only 
Ans. (c) 
In metal carbonyl organometallic compounds the bond between metal atom and carbon 
monoxide ligand has both ?? and ?? characters. 
 
 
Q5. Which of the following statements is not correct? 
(a) ?? ?? ?? ?? ?? is used as a catalyst in converting acetylene to acetaldehyde. 
(b) ?? ???? ?? ?? . ?? ?? ?? ?? on strong heating gives ?? ???? with the liberation of ????
?? and ?? ?? . 
(c) ?? ???? ?? ?? . ?? ?? ?? ?? on heating at ?????? ?? gives ?? ???? ?? ?? · ?? ?? ?? ?? . 
(d) On sublimation, black variety of ?????? changes to red variety. 
Ans. (c) 
Z n S O
4
. 7 H
2
O ?
?
?
Z n S O
4
· H
2
O ?
?
?
Z n S O
4
. 
???? . ????
?? ( ???? )
?? is diamagnetic. Which of the following reasons is correct? 
(a) Presence of one ???? as bridge group. 
(b) Presence of monodentate ligand. 
(c) Metal-metal ( ???? - ???? ) bond in molecule. 
(d) Resonance hybridization of ???? . 
Ans. (c) 
Q7. Amongst the following complexes, select the one having highest magnetic 
dipole moment. 
(a) [ ???? ( ?? ?? ?? )
?? ]
?? +
 
(b) [ ???? ( ?? ?? ?? )
?? ]
?? +
 
(c) [ ???? ( ?? ?? ?? )
?? ]
?? +
 
(d) [ ???? ( ?? ?? ?? )
?? ]
?? +
 
Ans. (b) 
Because Fe
2 +
 has four unpaired electrons. 
Q8. The co-ordination number and oxidation state of ???? in ?? ?? [ ???? ( ?? ?? ?? ?? )
?? ] are 
respectively 
(a) 6 and +3 
(b) 3 and 0 
(c) 4 and +2 
(d) 3 and +3 
Ans. (a) 
Co-ordination number of Cr
3 +
 ion is six because chromium ion is surrounded by three 
bidentate ligands. 
For oxidation state of central metal ion 
3 + ?? - 6 = 0 
[where, ?? is the oxidation state of central metal ion] 
Q9. Hybridization of ???? in ?? ?? [ ???? ( ???? )
?? ] is 
(a) ????
?? 
(b) ?? ?? ????
?? 
(c) ????
?? ? ?? ?? 
(d) ?? ?? ?? ?? 
Ans. (b) 
In the given complex of Fe
3 +
, as the co-ordination number is ' 6 ', there are two possibilities. 
It can be d
2
sp
3
 or sp
3
 d
2
. But the ligand attached with central metal ion, Fe
3 +
, is strong field 
ligand so it willpromate inner orbital complex, ?? 2
?? 3
. 
Q10. Transition metal compounds are usually coloured. This is due to the 
electronic transition 
(a) from ?? orbital to s-orbital 
(b) from d orbital to s-orbitals 
(c) from d orbital to p-orbital 
(d) within the d-orbitals 
Ans.  (d) 
Many ionic and covalent compounds of transition elements are coloured and this colouring 
property is due to d - d electronic excitation. The colour of the compound is complimentary 
to the colour absorbed. 
Q11. A compound has an empirical formula ???????? ?? . ?? ????
?? . When an aqueous 
solution of this compound is mixed with excess of silver nitrate, 2 moles of ?? ?? ???? 
precipitates per mole of the compound. On reaction with excess of ?? ???? , no ????
?? +
is 
detected. Hence the compound is 
(a) [ ???? ( ????
?? )
?? ????
?? ] ???? 
(b) [ ???? ( ????
?? )
?? ???? ] ????
?? 
(c) [ ???? ( ????
?? )
?? ????
?? ] 
(d) [ ???? ( ????
?? )
?? ????
?? ] ???? . ????
?? 
Ans. (b) As the moles of A g Cl precipitated is 2 and no NH
4
+
is detected on reaction with excess 
of HCl, so the compound would be [ Co ( NH
3
)
5
Cl ] Cl
2
. 
?  
Q12. Which of the given statements is not true for the following reaction? 
[ ???? ( ?? ?? ?? )
?? ]
?? +
+ ?? ????
?? ? [ ???? ( ????
?? )
?? ]
?? +
+ ?? ?? ?? ?? 
(a) It is a ligand-substitution reaction. 
(b) ????
?? is a relatively strong field ligand while ?? ?? ?? is a weak field ligand. 
(c) During the reaction, there is a change in colour from light blue to dark blue. 
(d) [ ???? ( ????
?? )
?? ]
?? +
 has a tetrahedral structure and is paramagnetic. 
Ans: (d) 
For ?
29
Cu, outermost shell has electronic configuration of 3 d
10
4 s
1
. 
? ? Electronic configuration of Cu
2 +
= 3 d
9
4 s
°
 
? 
But due to strong field ligand ( NH
3
), unpaired electron of 3 d
9
 jumps to 4 p. Hence, 
? ? Hybridisation of Cu
2 +
 in [ Cu ( NH
3
)
4
]
2 +
 is ds p
2
 and it gives the square planar geometry. 
 
Q13. Which of the following statement is incorrect? 
(a) Most four-coordinated complexes of ????
?? +
 ions are square planar rather than 
tetrahedral. 
(b) The [ ???? ( ?? ?? ?? )
?? ]
?? +
 ion is more paramagnetic than the [ ???? ( ???? )
?? ]
?? -
 ion. 
(c) Square planar complexes are more stable than octahedral complexes. 
(d) The [ ???? ( ???? )
?? ]
?? -
 ion is paramagnetic but [ ???? ( ???? )
?? ]
?? -
 ion is diamagnetic. 
Ans: ( d ) [ Fe ( CN )
6
]
4 -
 has Fe
2 +
 and have no unpaired electron, so it is diamagnetic and 
[ Fe ( CN )
6
]
3 -
 has Fe
3 +
 and having one unpaired electron, so it is paramagnetic. 
 
Q14.  Which of the following compound is not having synergic bonding? 
(A) ???? ( ???? )
?? 
(B) [ ???? ( ???? )
?? ]
?? -
 
(C) [ ???? ( ?? - ?? ?? ?? ?? )
?? ] 
(D) [ ?????? ?? ]
?? -
 
Ans: (D) [ CoF
6
]
3 -
 doesn't have synergic bonding due to lack of empty orbitals in F
-
. 
Q15. Which of the following is a low spin complex? 
(A) ???? ( ???? )
?? 
(B) [ ???? ( ????
?? )
?? ]
?? +
 
(C) [ ???? ( ????
?? )
?? ]
?? +
 
(D) All of these 
Ans: (D) CO , NH
3
 are strong ligands. So all are low spin complexes 
Q16.  Which of the following name is incorrect for the given complex. 
?? [ ???? ( ?? ?? ?? )
?? ( ?? ???? ?? )
?? ( ????
?? ) ] 
(A) Potassium diaquatrisothiocyanatonitrato ferrate (III) 
(B) Potassium diaquanitratotrithiocyanato- ?? - ferrate (III) 
(C) Potassium diaquatrithiocyanato- ?? -nitrito ferrate (III) 
(D) Potassium diaquatrisothiocyanatonitrato ferrate (II) 
Ans : (D) K [ Fe ( H
2
O )
2
( N CS )
3
NO
3
] 
Potassium di aqua-tri-isothiocynato-nitrato Ferrate (III) 
Q17. What is the hybridization of ???? in [ ???? ( ???? )
?? ] ? 
(A) ????
?? 
(B) ???? ?? ?? 
(C) ???? 
(D) ????
?? ?? ?? 
 
Ans: (B) Fe ? 26 
 
CO is a strong ligand. Pairing takes place. 
 
Q18.  Which of the following complex/molecule acts as a reducing agent? 
(A) [ ???? ( ????
?? )
?? ]
?? +
 
(B) [ ???? ( ???? )
?? ] 
(C) NO 
(D) All are 
Ans: (D) NO ? NO
+
, CO
2 +
? CO
3 +
 (Stable) 
Mn
+
can form stable complex with strong ligand CO. So, all are reducing agents 
 
Q19.  What is the hybridization of ???? in sodium thionitroprusside? 
(A) ????
?? ?? ?? 
(B) ?? ?? ?? ?? ?? 
Page 5


Solved Examples on Co-ordination 
Compounds 
JEE Mains 
Q1. The reaction between yttrium metal ?? and dilute hydrochloric acid produces 
?? ?? ( ?? ) and ?? ?? +
 ions. The molar ratio of yttrium used to hydrogen produced is 
(a) ?? : ?? 
(b) ?? : ?? 
(c) ?? : ?? 
(d) ?? : ?? 
Ans. (d) 
2Y
2 mol
+ 6HCl ? 2 Y Cl
3
+ 3 H
2
3 mol
 
???? . [ ???? ( ?? ?? ?? )
?? ]
?? +
 and [ ???? ( ???? )
?? ]
?? -
 differ in 
(a) geometry, magnetic moment 
(b) magnetic moment, colour 
(c) geometry, hybridization 
(d) hybridization, number of unpaired electrons 
Ans. (b) 
Q3. An aqueous solution containing 0.02 mole of [ ???? ( ????
?? )
?? ????
?? ] ???? and 0.02 mole 
of [ ???? ( ????
?? )
?? ???? ] ????
?? was prepared and its volume was made upto 2 litres. It was 
divided into two equal parts. 
?? st 
 part + excess ?? ?? ???? ?? ? [ ?? ] 
?? nd 
 part + excess ???????? ?? ? [ ?? ]. No. of moles of [ ?? ] and [ ?? ] are respectively 
(a) 0.01 and 0.01 
(b) 0.02 and 0.01 
(c) 0.01 and 0.02 
(d) 0.02 and 0.02 
Ans. (a) 
 Concentration =
 moles 
 volume 
=
. 02
2
= . 01 
Q4. In ???? ( ???? )
?? , the ???? - ?? bond possesses. 
(a) ?? character only 
(b) ionic character 
(c) both ?? and ?? character 
(d) ?? - character only 
Ans. (c) 
In metal carbonyl organometallic compounds the bond between metal atom and carbon 
monoxide ligand has both ?? and ?? characters. 
 
 
Q5. Which of the following statements is not correct? 
(a) ?? ?? ?? ?? ?? is used as a catalyst in converting acetylene to acetaldehyde. 
(b) ?? ???? ?? ?? . ?? ?? ?? ?? on strong heating gives ?? ???? with the liberation of ????
?? and ?? ?? . 
(c) ?? ???? ?? ?? . ?? ?? ?? ?? on heating at ?????? ?? gives ?? ???? ?? ?? · ?? ?? ?? ?? . 
(d) On sublimation, black variety of ?????? changes to red variety. 
Ans. (c) 
Z n S O
4
. 7 H
2
O ?
?
?
Z n S O
4
· H
2
O ?
?
?
Z n S O
4
. 
???? . ????
?? ( ???? )
?? is diamagnetic. Which of the following reasons is correct? 
(a) Presence of one ???? as bridge group. 
(b) Presence of monodentate ligand. 
(c) Metal-metal ( ???? - ???? ) bond in molecule. 
(d) Resonance hybridization of ???? . 
Ans. (c) 
Q7. Amongst the following complexes, select the one having highest magnetic 
dipole moment. 
(a) [ ???? ( ?? ?? ?? )
?? ]
?? +
 
(b) [ ???? ( ?? ?? ?? )
?? ]
?? +
 
(c) [ ???? ( ?? ?? ?? )
?? ]
?? +
 
(d) [ ???? ( ?? ?? ?? )
?? ]
?? +
 
Ans. (b) 
Because Fe
2 +
 has four unpaired electrons. 
Q8. The co-ordination number and oxidation state of ???? in ?? ?? [ ???? ( ?? ?? ?? ?? )
?? ] are 
respectively 
(a) 6 and +3 
(b) 3 and 0 
(c) 4 and +2 
(d) 3 and +3 
Ans. (a) 
Co-ordination number of Cr
3 +
 ion is six because chromium ion is surrounded by three 
bidentate ligands. 
For oxidation state of central metal ion 
3 + ?? - 6 = 0 
[where, ?? is the oxidation state of central metal ion] 
Q9. Hybridization of ???? in ?? ?? [ ???? ( ???? )
?? ] is 
(a) ????
?? 
(b) ?? ?? ????
?? 
(c) ????
?? ? ?? ?? 
(d) ?? ?? ?? ?? 
Ans. (b) 
In the given complex of Fe
3 +
, as the co-ordination number is ' 6 ', there are two possibilities. 
It can be d
2
sp
3
 or sp
3
 d
2
. But the ligand attached with central metal ion, Fe
3 +
, is strong field 
ligand so it willpromate inner orbital complex, ?? 2
?? 3
. 
Q10. Transition metal compounds are usually coloured. This is due to the 
electronic transition 
(a) from ?? orbital to s-orbital 
(b) from d orbital to s-orbitals 
(c) from d orbital to p-orbital 
(d) within the d-orbitals 
Ans.  (d) 
Many ionic and covalent compounds of transition elements are coloured and this colouring 
property is due to d - d electronic excitation. The colour of the compound is complimentary 
to the colour absorbed. 
Q11. A compound has an empirical formula ???????? ?? . ?? ????
?? . When an aqueous 
solution of this compound is mixed with excess of silver nitrate, 2 moles of ?? ?? ???? 
precipitates per mole of the compound. On reaction with excess of ?? ???? , no ????
?? +
is 
detected. Hence the compound is 
(a) [ ???? ( ????
?? )
?? ????
?? ] ???? 
(b) [ ???? ( ????
?? )
?? ???? ] ????
?? 
(c) [ ???? ( ????
?? )
?? ????
?? ] 
(d) [ ???? ( ????
?? )
?? ????
?? ] ???? . ????
?? 
Ans. (b) As the moles of A g Cl precipitated is 2 and no NH
4
+
is detected on reaction with excess 
of HCl, so the compound would be [ Co ( NH
3
)
5
Cl ] Cl
2
. 
?  
Q12. Which of the given statements is not true for the following reaction? 
[ ???? ( ?? ?? ?? )
?? ]
?? +
+ ?? ????
?? ? [ ???? ( ????
?? )
?? ]
?? +
+ ?? ?? ?? ?? 
(a) It is a ligand-substitution reaction. 
(b) ????
?? is a relatively strong field ligand while ?? ?? ?? is a weak field ligand. 
(c) During the reaction, there is a change in colour from light blue to dark blue. 
(d) [ ???? ( ????
?? )
?? ]
?? +
 has a tetrahedral structure and is paramagnetic. 
Ans: (d) 
For ?
29
Cu, outermost shell has electronic configuration of 3 d
10
4 s
1
. 
? ? Electronic configuration of Cu
2 +
= 3 d
9
4 s
°
 
? 
But due to strong field ligand ( NH
3
), unpaired electron of 3 d
9
 jumps to 4 p. Hence, 
? ? Hybridisation of Cu
2 +
 in [ Cu ( NH
3
)
4
]
2 +
 is ds p
2
 and it gives the square planar geometry. 
 
Q13. Which of the following statement is incorrect? 
(a) Most four-coordinated complexes of ????
?? +
 ions are square planar rather than 
tetrahedral. 
(b) The [ ???? ( ?? ?? ?? )
?? ]
?? +
 ion is more paramagnetic than the [ ???? ( ???? )
?? ]
?? -
 ion. 
(c) Square planar complexes are more stable than octahedral complexes. 
(d) The [ ???? ( ???? )
?? ]
?? -
 ion is paramagnetic but [ ???? ( ???? )
?? ]
?? -
 ion is diamagnetic. 
Ans: ( d ) [ Fe ( CN )
6
]
4 -
 has Fe
2 +
 and have no unpaired electron, so it is diamagnetic and 
[ Fe ( CN )
6
]
3 -
 has Fe
3 +
 and having one unpaired electron, so it is paramagnetic. 
 
Q14.  Which of the following compound is not having synergic bonding? 
(A) ???? ( ???? )
?? 
(B) [ ???? ( ???? )
?? ]
?? -
 
(C) [ ???? ( ?? - ?? ?? ?? ?? )
?? ] 
(D) [ ?????? ?? ]
?? -
 
Ans: (D) [ CoF
6
]
3 -
 doesn't have synergic bonding due to lack of empty orbitals in F
-
. 
Q15. Which of the following is a low spin complex? 
(A) ???? ( ???? )
?? 
(B) [ ???? ( ????
?? )
?? ]
?? +
 
(C) [ ???? ( ????
?? )
?? ]
?? +
 
(D) All of these 
Ans: (D) CO , NH
3
 are strong ligands. So all are low spin complexes 
Q16.  Which of the following name is incorrect for the given complex. 
?? [ ???? ( ?? ?? ?? )
?? ( ?? ???? ?? )
?? ( ????
?? ) ] 
(A) Potassium diaquatrisothiocyanatonitrato ferrate (III) 
(B) Potassium diaquanitratotrithiocyanato- ?? - ferrate (III) 
(C) Potassium diaquatrithiocyanato- ?? -nitrito ferrate (III) 
(D) Potassium diaquatrisothiocyanatonitrato ferrate (II) 
Ans : (D) K [ Fe ( H
2
O )
2
( N CS )
3
NO
3
] 
Potassium di aqua-tri-isothiocynato-nitrato Ferrate (III) 
Q17. What is the hybridization of ???? in [ ???? ( ???? )
?? ] ? 
(A) ????
?? 
(B) ???? ?? ?? 
(C) ???? 
(D) ????
?? ?? ?? 
 
Ans: (B) Fe ? 26 
 
CO is a strong ligand. Pairing takes place. 
 
Q18.  Which of the following complex/molecule acts as a reducing agent? 
(A) [ ???? ( ????
?? )
?? ]
?? +
 
(B) [ ???? ( ???? )
?? ] 
(C) NO 
(D) All are 
Ans: (D) NO ? NO
+
, CO
2 +
? CO
3 +
 (Stable) 
Mn
+
can form stable complex with strong ligand CO. So, all are reducing agents 
 
Q19.  What is the hybridization of ???? in sodium thionitroprusside? 
(A) ????
?? ?? ?? 
(B) ?? ?? ?? ?? ?? 
(C) ????
?? ?? 
(D) No hybridization 
Ans: (B) It has 5 CN
-
ligands (strong) Fe
2 +
, pairing takes place. So, d
2
sp
3
 
 
Q20.  What is correct name of linkage isomer of [ ???? ( ?? ?? ?? )
?? ( ????
?? ) ] ????
?? . 
(A) Pentaaquanitro-'O' chromium (III) bromide 
(B) Pentaaquanitro chromium (III) bromide 
(C) Pentaaquonitro chromium (III) bromide 
(D) Pentaaquanitrito-'O" chromium (II) bromide 
Ans: (A) IUPAC of [ Cr ( H
2
O )
5
ON O ] Br
2
 Penta-aquonitrito-O chromium(III) Bromide 
 
Q21.  The effective atomic number of ???? ( ???? )
?? is 35 . It does not attain stability by 
(A) Oxidation of [ ???? ( ???? )
?? ] 
(B) Reduction of [ ???? ( ???? )
?? ] 
(C) Dimerization of [ ???? ( ???? )
?? ] 
(D) By both (B) and (C) 
Ans: (B) By reduction or dimension, it can attain EAN of 36 . So, oxidation doesn't lead to 
stability. 
JEE Advanced 
 
Single Correct Type 
Q22.  Select the correct order of ?? - ?? bond order in following complexes. 
(A) [ ?? ( ????
?? ( ?????? ?? )
?? ( ???? ?? ?? ) ] > [ ?? ( ???? )
?? ( ?????? ?? )
?? ] > [ ?? ( ???? )
?? ( ?????? ?? ) ( ?????? ?? )
?? ] 
(B) [ ?? ( ???? )
?? ( ?????? ?? )
?? ( ???? ?? ?? )
?? ] > [ ?? ( ???? )
?? ( ?????? ?? )
?? ] > [ ?? ( ???? )
?? ( ?????? ?? )
?? ( ?????? ?? ) ] 
(C) [ ?? ( ???? )
?? ( ?????? ?? ) ( ?????? ?? )
?? ] = [ ?? ( ???? )
?? ( ?????? ?? )
?? ] < [ ?? ( ???? )
?? ( ?????? ?? )
?? ( ?????? ?? ) ] 
(D) [ ?? ( ???? )
?? ( ?????? ?? )
?? ] > [ ?? ( ????
?? ( ?????? ?? )
?? ( ?? ???? ?? ) ] > [ ?? ( ???? )
?? ( ?????? ?? ) ( ?? ???? ?? )
?? ] 
Ans: (D) [ CoF
6
]
3 -
 doesn't have synergic bonding due to lack of empty orbitals in F
-
. 
 
Q23.  What is the hybridization of ???? in [ ???? (???? )
?? ] ? 
(A) ????
?? 
(B) ???? ?? ?? 
(C) ???? 
(D) ????
?? ?? ?? 
Ans: (D) CO , NH
3
 are strong ligands. So all are low spin complexes