Organic Chemistry Some Basic Principles CBSE Questions & Answers

Organic Chemistry Some Basic Principles

This is Chemistry Class 11 Organic Chemistry Some Basic Principles CBSE Questions & Answers. There are 15 questions in this test with each question having around four answer choices.

Questions & Answers

1
The technique that is extensively used to separate mixtures into their components, purify compounds and also to test the purity of compounds is
  • A
    Chromatography
    Correct
  • B
    fractional distillation
  • C
    Differential Extraction
  • D
    steam distillation
2
Aniline is separated by technique from aniline . water mixture
  • A
    Chromatography
  • B
    Differential Extraction
  • C
    steam distillation
    Correct
  • D
    fractional distillation
3
Sodium cyanide, sulphide and halide,( -CN, -S and -H, coming from organic compound) so formed on sodium fusion are extracted from the fused mass by boiling it with distilled water. This is called
  • A
    Sodium fusion ion extraction
  • B
    Double distillate
  • C
    sodium fusion extract
    Correct
  • D
    ion extract after sodium fusion
4
Geometrical isomers and Optical isomers are:
  • A
    stereoisomer
    Correct
  • B
    chain isomers
  • C
    position isomerism.
  • D
    functional isomers
5
When an organic compound is present in an aqueous medium, it is separated by
  • A
    fractional distillation
  • B
    Differential Extraction
    Correct
  • C
    steam distillation
  • D
    Chromatography
6
Electrophilic addition reactions proceed in two steps. The first step involves the addition of an electrophile. Name the type of intermediate formed in the first step of the following addition reaction. \({{\text{H}}_{\text{3}}}{\text{C}}---{\text{HC }} = {\text{ C}}{{\text{H}}_{\text{2}}} + {\text{ }}{{\text{H}}^ + } \to ?\)
  • A
    tex}{\text{2}}^\circ {/tex} Carbanion
  • B
    \({\text{1}}^\circ \) Carbanion
  • C
    \({\text{2}}^\circ \) Carbocation
    Correct
  • D
    \({\text{1}}^\circ \) Carbocation
7
In general, in the molecules containing multiple bonds,_____ provide the most reactive centres. Choose the most appropriate one.
  • A
    p orbitals
  • B
    hyperconjugation
  • C
    π bonds
    Correct
  • D
    σ bond
8
Covalent bond can undergo fission in two different ways. The correct representation involving a heterolytic fission of \({\text{C}}{{\text{H}}_{\text{3}}}---{\text{Br}}\) is
Question 8 figure 1
  • A
    (i)
  • B
    (iv)
  • C
    (jjj)
  • D
    (ii)
    Correct
9
The addition of HCl to an alkene proceeds in two steps. The first step is the attack of H+ ion to portion which can be shown as
Question 9 figure 1
  • A
    (ii)
    Correct
  • B
    (jjj)
  • C
    (i)
  • D
    (iv)
10
For testing halogens in an organic compound with \({\text{AgN}}{{\text{O}}_{\text{3}}}\)solution, sodium extract (Lassaigne’s test) is acidified with dilute \({\text{HN}}{{\text{O}}_{\text{3}}}.\)What will happen if a student acidifies the extract with dilute \({{\text{H}}_{\text{2}}}{\text{S}}{{\text{O}}_{\text{4}}}\)in place of dilute HNO3?
  • A
    green ppt. of \({\text{A}}{{\text{g}}_{\text{2}}}{\text{S}}{{\text{O}}_{\text{4}}}\)will be formed
  • B
    \({\text{S}}{{\text{O}}_{\text{2}}}\)will be formed
  • C
    White ppt. of \({\text{A}}{{\text{g}}_{\text{2}}}{\text{S}}{{\text{O}}_{\text{4}}}\)will be formed.
    Correct
  • D
    White ppt. of \({\text{A}}{{\text{g}}_{\text{2}}}{\text{S}}\) will be formed
11
Delocalisation of σ electrons of C -H bond of an alkyl group directly attached to an atom of unsaturated system or to an atom with an unshared p orbital is called:
  • A
    Hyperconjugation
    Correct
  • B
    Substitution reactions
  • C
    Elimination reactions
  • D
    Rearrangement reactions
12
Which of the following compounds contain all the carbon atoms in the same hybridisation state?
  • A
    \({\text{C}}{{\text{H}}_{\text{2}}} = {\text{ C }} = {\text{ C}}{{\text{H}}_{\text{2}}}\)
  • B
    \({\text{C}}{{\text{H}}_{\text{3}}}---{\text{C }} \equiv {\text{ C}}---{\text{ C}}{{\text{H}}_{\text{3}}}\)
  • C
    \({\text{H}}---{\text{C }} \equiv {\text{ C}}---{\text{C }} \equiv {\text{ C}}---{\text{H}}\)
    Correct
  • D
    \({\text{C}}{{\text{H}}_{\text{2}}} = {\text{ CH}}---{\text{C }} \equiv {\text{ CH}}\)
13
In which of the following representations given below spatial arrangement of group/ atom different from that given in structure ‘A’?
Question 13 figure 1
  • A
    (i) and (iv)
  • B
    (i) and (iii)
    Correct
  • C
    (i) and (ii)
  • D
    (ii) and (iii)
14
Why Kjeldahl method cannot be used for the estimation of nitrogen present in DNA and RNA? Choose the most appropriate option.
  • A
    DNA and RNA have deoxyribose and ribose which interferes in the Kjeldahl method.
  • B
    DNA and RNA have phosphorous which interferes in the Kjeldahl method
  • C
    Nitrogen present in rings, azo groups and nitro groups of DNA and RNA cannot be removed as ammonia. ..
    Correct
  • D
    The bases present in the DNA and RNA structures doesnot allow them to participate in the Kjeldahl method.
15
One of the following compounds is used in the estimation of oxygen
  • A
    silver nitrate
  • B
    copper oxide
  • C
    iodine pentoxide
    Correct
  • D
    sodium perooxide