What is the coordination entity formed when excess of aqueons KCN is added to an aqueous solution of copper sulphate? Why is it that no precipitate of copper sulphide is obtained when H2S (g) is passed through this solution?
First cupric cyanide is formed which decomposes to give cuprous cyanide and cyanogen gas. Cuprous cyanide dissolves in excess of potassium cyanide to form the complex, K3[Cu(CN)4],
Thus, coordination entity formed in the above reaction is [Cu(CN)4]3-. As CN– is a strong ligand, the complex ion is highly stable and does not dissociate/ionize to give Cu2+ ions. Hence, no precipitate,with H2S is formed.
When 1 mol CrCl3.6H2O is treated with excess of AgNO3, 3 mol of AgCl are obtained. The formula of the complex is
What is meant by unidentate didentate and ambidentate ligands? Give two examples for each.
Assertion (A): [Cr(H2O)6]Cl2 and [Fe(H2O)6]Cl2 are reducing in nature. Reason (R): Unpaired electrons are present in their J-orbitals.
Calculate the overall complex dissociation equilibrium constant for the Cu(NH3)42+ ion, given that β4 for this complex is 2.1 x 1013.
Write the IUPAC names of the following coordination compounds:
(i)[Co(NH3)6]Cl3
(ii)[Co(NH3)5Cl]Cl2
(iii)K3[Fe(CN)6l
(iv)K3lFe(C2O4)3]
(v)K2[PdCl4]
(vi)[Pt(NH3)2Cl(NH2CH3)]Cl
On the basis of crystal field theory explain why Co(III) forms paramagnetic octahedral complex with weak field ligands whereas it forms diamagnetic octahedral complex with strong field ligands.
The colour of the coordination compounds depends on the crystal field splitting. What will be the correct order of absorption of wavelength of
A complex of the type [M(AA)2X2]n+ is known to be optically active. What does this indicate about the structure of the complex? Give one example of such complex.
In the following questions, a statement of Assertion (A) followed by a statement of Reason (R) is given. Choose the correct option out of the following choices.
(a) Assertion and Reason both are true, Reason is the correct explanation of Assertion.
(b) Assertion and Reason both are true but Reason is not the correct explanation of Assertion.
(c) Assertion is true, Reason is false.
(d) Assertion is false, Reason is true.
Assertion (A): Toxic metal ions are removed by the chelating ligands. Reason (R): Chelate complexes tend to be more stable.
Which of the following options are correct for [Fe(CN)6]3- complex?
(a) d2sp3 hybridisation
(b) sp3d2 hybridisation
(c) Paramagnetic
(d) Diamagnetic
Arrange following complex ions in increasing order of crystal field splitting energy (A0):
[Cr(Cl)6]3-, [Cr(CN)6]3-, [Cr(NH3)6]3+
What is meant by stability of a coordination compound in solution? State the factors which govern stability of complexes.
Match the complex species given in Column I with the possible isomerism given in Column II and assign the correct code:
Write all the geometrical isomers of [Pt(NH3)(Br)(Cl) (Py)] and how many of these will exhibit optical isomerism?
Which of the following complexes show linkage isomerism?
(a) [CO(NH3)5(NO2)]2+ (b) [CO(H2O)5CO]3+
(c) [Cr(NH3)5SCN]2+ (d) [Fe(en)2Cl2]+
Give the electronic configuration of the following complexes on the basis of crystal field splitting theory.
[COF6]3-, [Fe(CN)6]4- and [Cu(NH3)6]2+.
What will be the correct order for the wavelengths of absorption in the visible region for the following:[Ni(NO2)6]4-, [Ni(NH3)6]2+, [Ni(H20)6]2+?
The stabilization of coordination compounds due to chelation is called the chelate effect. Which of the following is the most stable complex species?
An aqueous pink solution of cobalt (II).chloride changes to deep biue on addition of excess of HCl. This is because
(a) [Co(H2O)6]2+ is transformed into [CoCl6]4-
(b) [CO(H2O)6]2+ is transformed into [COCl4]2-
(c) tetrahedral complexes have smaller crystal field splitting than octahedral complexes
(d) tetrahedral complexes have larger crystal field splitting than octahedral complex
Arrange the following complexes in the increasing order of conductivity of their solution:
[Co(NH3)3Cl3], [CO(NH3)4Cl2]Cl, [CO(NH3)6]C13, [Cr(NH3)5Cl]Cl2
Match the coordination compounds given in Column I with the central metal atoms given in Column II and assign the correct code:
Assertion (A): Linkage isomerism arises in coordination compounds containing ambidentate ligand.
Reason (R): Ambidentate ligand has two different donor atoms.
Assertion (A): Complexes of MX6 and MX5L type (X and L are unidentate) do not show geometrical isomerism.
Reason (R): Geometrical isomerism is not shown by complexes of coordination number 6.
Explain on the basis of valence bond theory that [Ni(CN)4]2- ion with square planar structure is diamagnetic and the[Ni(CN)4]2- ion with tetrahedral geometry is paramagnetic.
How many geometrical isomers are possible in . the following coordination entities?
(i) [Cr(C2O4)3]3- (ii) [CoCl3(NH3)3]
What is crystal field splitting energy? How does the magnitude of Δ0 decide the actual configuration of d-orbitals in a coordination entity?
How many ions are produced from the complex Co(NH3)6Cl2 in solution?
(i) 6
(ii) 4
(iii)3
(iv)2
What is the relationship between observed colour of the complex and the wavelength of light absorbed by the complex?
Why are different colours observed in octahedral and tetrahedral complexes for the same metal and same ligands?
Draw all the isomers (geometrical and optical) of
(i)[CoCl2(en)2]+
(ii)[Co(NH3) Cl (en)2]2+
(iii) [Co(NH3)2Cl2(en)]+
Amongst the following ions? Which one has the highest magnetic moment value:
(i) [Cr(H2O)6]3+
(ii) [Fe(H20)6]2+ (iii) [Zn(H20)6]2+
Amongst the following, the most stable complex is:
(i) [Fe(H2O)6] (ii) [Fe(NH3)6]3+
(iii) [Fe(C2O4)3]3- (iv) [FeCl6]3-
CoSO4Cl.5NH3 exists in two isomeric forms ‘A' and ‘B'. Isomer ‘A' reacts with AgNO3 to give white precipitate, but does not react with BaCl2. Isomer ‘B' gives white precipitate with BaCl2 but does not react with AgNO3. Answer the following questions.
(i) Identify A' and B' and write their structural formulas.
(ii) Name the type of isomerism involved.
(iii) Give the IUPAC name of A' and B'.
[Fe(H2O)6]3+is strongly paramagnetic whereas [Fe(CN)6]3-is weakly paramagnetic. Explain.
Identify the correct statements for the behaviour of ethane-1, 2-diamine as a ligand.
(a) It is a neutral ligand (b) It is a didentate ligand
(c) It is a chelating ligand (d) It is a unidentate ligand
Match the complex ions given in Column I with the colours given in Column II and assign the correct code:
A coordination compound CrCl3.4H2O precipitates silver chloride when treated with silver nitrate. The molar conductance of its solution corresponds to a total of two ions. Write structural formula of the compound and name it.
