Advertisements
Advertisements
प्रश्न
What is the coordination entity formed when excess of aqueous 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?
Advertisements
उत्तर
Under the given conditions, cupric cyanide is initially generated, which then decomposes to provide cuprous cyanide and cyanogen gas. Cuprous cyanide subsequently dissolves in an excess of potassium cyanide to provide the complex K3[Cu(CN)4].
\[\ce{CuSO4 + 2KCN -> Cu(CN)2 + K2SO4 \times 2}\]
\[\ce{2Cu(CN)2 -> Cu2(CN)2 + (CN)2}\]
\[\ce{Cu2(CN)2 + 6KCN -> 2K3[Cu(CN)4]}\]
_____________________________________________________
\[\ce{2CuSO4 + 10KCN -> 2K3[Cu(CN)4] + 2K2SO4 + (CN)2}\]
So, the coordination entity formed is [Cu(CN)4]3−.
The CN− is a strong field ligand; the complex ion is highly stable and can’t dissociate to give copper ions. Hence, no precipitate of copper sulphide is formed when H2S(g) is passed through this solution.
संबंधित प्रश्न
What is meant by unidentate ligand?
Give the oxidation state, d-orbital occupation and coordination number of the central metal ion in the following complex:
[Mn(H2O)6]SO4
Predict the co-ordination No. of cs+ ion if `r_(Cs)^+` = 1.69Å and `r_(Cl)^-` = 1.81Å.
Write IUPAC names of the following compounds:

What happens when PCl5 is heated? Write the equations involved.
Following compounds are given to you :
2-Bromopentane, 2-Bromo-2-methylbutane, 1-Bromopentane
1) Write the compound which is most reactive towards SN2 reaction.
2) Write the compound which is optically active.
3) Write the compound which is most reactive towards β-elimination reaction.
Write structures of compounds A and B of the following reaction :

The coordination number of Cr in [Cr(NH3)3(H2O)3]Cl3 is ___________.
What is the coordination number of chromium in \[\ce{[Cr(NH3)2(H2O2)2]Cl3}\]?
Which of the following complexes formed by \[\ce{Cu^2+}\] ions is most stable?
When 1 mol \[\ce{CrCl3.6H2O}\] is treated with excess of \[\ce{AgNO3}\], 3 mol of \[\ce{AgCl}\] are obtained. The formula of the complex is ______.
Arrange the following complexes in the increasing order of conductivity of their solution:
[Co(NH3)3Cl3], [Co(NH3)4Cl2]Cl, [Co(NH3)6]Cl3, [Cr(NH3)5Cl]Cl2
Match the complex ions given in Column I with the colours given in Column II and assign the correct code:
| Column I (Complex ion) | Column II (Colour) |
| A. \[\ce{[Co(NH3)6]^{3+}}\] | 1. Violet |
| B. \[\ce{[Ti(H2O)6]^{3+}}\] | 2. Green |
| C. \[\ce{[Ni(H2O)6]^{2+}}\] | 3. Pale blue |
| D. \[\ce{(Ni(H2O)4 (en)]^{2+} (aq)}\] | 4. Yellowish orange |
| 5. Blue |
Assertion: \[\ce{Cr(H2O)6]Cl2 and [Fe(H2O)6]Cl2}\] are reducing in nature.
Reason: Unpaired electrons are present in their d-orbitals.
The nature of hybridisation in the ammonia molecule is
How many ions are produced from the complex Co(NH3)6]Cl2 in solution?
Given below are two statements.
Statement I: In CuSO4·5H2O, Cu-O bonds are present.
Statement II: In CuSO4·5H2O, ligands coordinating with Cu(II) ion are O- and S-based ligands.
In light of the above statement, choose the correct answer from the options given below.
What is meant by the chelate effect? Give an example.
Explain the following, giving two examples:
Homoleptic
Statement I: [Co(NH3)6]3+ is a homoleptic compleх whereas [Co(NH3)4Cl2]+ is a heteroleptic complex.
Statement II: Complex [Co(NH3)6]3+ has only one kind of ligands but [Co(NH3)4Cl2]+ has more than one kind of ligands.
In the light of the above statements, Choose the correct answer form the options given below.
