Chemistry Class-11: Chapter – 12. The Organic Chemistry Some Basic Principles and Techniques Part – 8 (For CBSE, ICSE, IAS, NET, NRA 2022)

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Question: 48

By mistake, an alcohol (boiling point ) was mixed with a hydrocarbon (boiling point ) . Suggest a suitable method to separate the two compounds. Explain the reason for your choice.

Answer:

Simple distillation can be used because the two compounds have a difference of more than in their boiling points and both the liquids can be distilled without any decomposition.

Question: 49

Which of the two structures (A) and (B) given below is more stabilized by resonance? Explain.

Answer:

Resonating structures are as follows:

(A)

Resonating Structures

(B)

Resonating Structures
Resonating Structures

Structure ‘B’ is more stabilized as it does not involve charge separation.

IV. Matching Type

In the following questions more than one correlation is possible between options of Column I and Column II. Make as many correlations as you can.

Question: 50

Match the type of mixture of compounds in Column I with the technique of separation/purification given in Column II.

Match the Type of Mixture of Compounds in Column I with the Technique of Separation/Purification Given in Column II
Column IColumn I
(i)Two solids which have different solubility՚s in a solvent and which do not undergo reaction when dissolved in it.aSteam distillation
(ii)Liquid that decomposes at its boiling pointbFractional distillation
(iii)Steam volatile liquidcSimple distillation
(iv)Two liquids which have boiling points close to each otherdDistillation under reduced pressure
(v)Two liquids with large difference in boiling pointseCrystallization

Answer:

(i) ⇾ (e) (ii) ⇾ (d) (iii) ⇾ (a) (iv) ⇾ (b) (v) ⇾ (c)

Question: 51

Match the terms mentioned in Column I with the terms in Column II.

Match the Terms Mentioned in Column I with the Terms in Column II
Column IColumn I
(i)CarbocationaCyclohexane and 1- hexane
(ii)NucleophilebConjugation of electrons of bond with empty p-orbital present at adjacent positively charged carbon.
(iii)Hyperconjugationc hybridised carbon with empty p-orbital
(iv)IsomersdEthyne
(v) hybridisationeSpecies that can receive a pair of electrons
(vi)ElectrophileSpecies that can supply a pair of electrons

Answer:

(i) ⇾ (c) (ii) ⇾ (f) (iii) ⇾ (b) (iv) ⇾ (a) (v) ⇾ (d) (vi) ⇾ (e)

Question: 52

Match Column I with Column II.

Match Column I with Column II
Column IColumn I
(i)Duma՚s methoda
(ii)Kjeldahl methodbSilica gel
(iii)Carious methodcNitrogen gas
(iv)ChromatographydFree radicals
(v)HemolysiseAmmonium sulphate

Answer:

(i) ⇾ (c) (ii) ⇾ (e) (iii) ⇾ (a) (iv) ⇾ (b) (v) ⇾ (d)

Question: 53

Match the intermediates given in Column I with their probable structure in Column II.

Match the Intermediates Given in Column I with Their Probable Structure in Column II
Column IColumn I
(i)Free radicalaTrigonal planar
(ii)CarbocationbPyramidal
(iii)CarbanioncLinear

Answer:

(i) ⇾ (a) , (ii) ⇾ (a) (iii) ⇾ (b)

Question: 54

Match the Column I with Column II
Column IColumn I
(i)
Compound to Match
a
(ii)bStable due to resonance
(iii)cDestabilized due to inductive effect
(iv)Stabilized by hyperconjugationdA secondary carbocation

Answer:

(i) ⇾ (a) , (b) , (d) (ii) ⇾ (b) (iii) ⇾ (b) (iv) ⇾ (c) , (d)