Class 12 Chemistry - Chapter Coordination Compounds NCERT Solutions | Predict the number of unpaired electrons

[NiCl₄]^2- is paramagnetic while [Ni(CO)₄] is diamagnetic though both are tetrahedral. Why?

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.

Draw figure to show the splitting of d orbitals in an octahedral crystal field.

Write down the IUPAC name for each of the following complexes and indicate the oxidation state, electronic configuration and coordination number. Also give stereochemistry and magnetic moment of the complex:

(i) K[Cr(H₂O)₂(C₂O₄)₂].3H₂O

(ii) [Co(NH₃)₅Cl]Cl₂

(iii) CrCl₃(py)₃

(iv) Cs[FeCl₄]

(v) K₄[Mn(CN)₆]

The oxidation number of cobalt in K[Co(CO)₄] is

(i) +1

(ii) +3

(iii) -1

(iv) -3

[Cr(NH₃)₆]³⁺ is paramagnetic while [Ni(CN)₄]^2- is diamagnetic.  Explain why?

Discuss the nature of bonding in metal carbonyls.

Discuss the nature of bonding in the following coordination entities on the basis of valence bond theory:

(i) [Fe(CN)₆]^4-

(ii) [FeF₆]^3-

(iii) [Co(C₂O₄)3]^3-

(iv) [CoF₆]^3-

Write the formulas for the following coordination compounds:

(i) Tetraamminediaquacobalt (III) chloride

(ii) Potassium tetracyanonickelate(II)

(iii) Tris(ethane-1,2-diamine) chromium(III) chloride

(iv) Amminebromidochloridonitrito-N-platinate(II)

(v) Dichloridobis(ethane-1,2-diamine)platinum(IV) nitrate

(vi) Iron(III) hexacyanoferrate(II)

Using IUPAC norms write the formulas for the following:

(i) Tetrahydroxozincate(II)

(ii) Potassium tetrachloridopalladate(II)

(iii) Diamminedichloridoplatinum(II)

(iv) Potassium tetracyanonickelate(II)

(v) Pentaamminenitrito-O-cobalt(III)

(vi) Hexaamminecobalt(III) sulphate

(vii) Potassium tri(oxalato)chromate(III)

(viii) Hexaammineplatinum(IV)

(ix) Tetrabromidocuprate(II)

(x) Pentaamminenitrito-N-cobalt(III)

For the reaction R → P, the concentration of a reactant changes from 0.03 M to 0.02 M in 25 minutes. Calculate the average rate of reaction using units of time both in minutes and seconds.

(i) Write structures of different isomeric amines corresponding to the molecular formula, C4H11N

(ii) Write IUPAC names of all the isomers.

(iii) What type of isomerism is exhibited by different pairs of amines?

Why are solids rigid?

Write any two characteristics of Chemisorption.

Write the structures of the following compounds.

(i) α-Methoxypropionaldehyde

(ii) 3-Hydroxybutanal

(iii) 2-Hydroxycyclopentane carbaldehyde

(iv) 4-Oxopentanal

(v) Di-sec-butyl ketone

(vi) 4-Fluoroacetophenone

Which of the ores mentioned in Table 6.1 can be concentrated by magnetic separation method?

Why are pentahalides more covalent than trihalides?

Silver atom has completely filled d orbitals (4d10) in its ground state. How can you say that it is a transition element?

Glucose or sucrose are soluble in water but cyclohexane or benzene (simple six membered ring compounds) are insoluble in water. Explain.

Write structures of the following compounds:

(i) 2-Chloro-3-methylpentane

(ii) 1-Chloro-4-ethylcyclohexane

(iii) 4-tert. Butyl-3-iodoheptane

(iv) 1,4-Dibromobut-2-ene

(v) 1-Bromo-4-sec. butyl-2-methylbenzene

Three electrolytic cells A,B,C containing solutions of ZnSO₄, AgNO₃ and CuSO₄, respectively are connected in series. A steady current of 1.5 amperes was passed through them until 1.45 g of silver deposited at the cathode of cell B. How long did the current flow? What mass of copper and zinc were deposited?

A solution of Ni(NO₃)₂ is electrolysed between platinum electrodes using a current of 5 amperes for 20 minutes. What mass of Ni is deposited at the cathode?

How much electricity is required in coulomb for the oxidation of

(i) 1 mol of H₂O to O₂.

(ii) 1 mol of FeO to Fe₂O₃.

Define thermoplastics and thermosetting polymers with two examples of each.

How much electricity in terms of Faraday is required to produce

(i) 20.0 g of Ca from molten CaCl₂.

(ii) 40.0 g of Al from molten Al₂O₃.

How much charge is required for the following reductions:

(i) 1 mol of Al³⁺ to Al.

(ii) 1 mol of Cu²⁺ to Cu.

(iii) 1 mol of MnO₄^- to Mn²⁺.

Conductivity of 0.00241 M acetic acid is 7.896 × 10 ^{- 5} S cm ^{- 1}. Calculate its molar conductivity and if A_m^º for acetic acid is 390.5 S cm² mol ^{- 1}, what is its dissociation constant?

Explain how rusting of iron is envisaged as setting up of an electrochemical cell.

What is the role of desorption in the process of catalysis?

Write the chemistry of recharging the lead storage battery, highlighting all the materials that are involved during recharging.