Chemistry

Organic Chemistry Fundamentals

237 Questions

Organic chemistry fundamentals cover the structure, properties, and reactions of carbon containing compounds. The questions explore functional groups, isomerism, homologous series, and basic reaction mechanisms. This forms the basis of general chemistry across multiple examination formats.

Functional groupsIsomerism typesHomologous seriesCycloalkanesOrganic monomers

Organic Chemistry Fundamentals Questions

Multiple choice

Epimerism is an isomerism that occurs depending on whcih of the following?

  1. Presence of asymmetric carbon atom.

  2. Spatial orientation of groups of single carbon atom.

  3. Orientation of H-OH group in C1 and C4.

  4. Rotation of plane of polarized light.

  5. Spatial arrangement of groups in asymmetric carbon atoms.
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Difference in spatial orientation of groups on a single asymmetric carbon of a molecule having more than one asymmetric carbon. For example, glucose and galactose are 4 epimers of each other differing with respect to groups on C4.

Multiple choice

Which of the following statements is/are correct?

A. 1-Chloro-2,3-pentadiene has no chiral carbon atoms, yet it is a chiral molecule. B. A newly discovered compound is through to be chiral, but shows no rotation in a specific solvent. This means that the compound is assuredly achiral. C. When a chiral molecule reacts to give a chiral molecule, the product is always racemic.

  1. Only A

  2. Only B

  3. Only C

  4. A and C

  5. B and C
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

This statement is correct because the molecule as whole is chiral since this molecule and its mirror image are non-superimposable.

Multiple choice

Which of the following statements is/are wrong?

A. 1-Methoxypropane and 2-methoxypropane are metamers. B. An optically active substance must be achiral. C. m-Chlorobromobenzene and m-bromochlorobenzene are isomers.

  1. A and B

  2. A and C

  3. B and C

  4. A, B and C

  5. Only A
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Statements A, B and C are incorrect. 1-Methoxypropane and 2-methoxypropane are positional isomers , an optically active substance must be chiral and  Isomers are molecules that have the same molecular formula, but have a different arrangement of the atoms in space.

Multiple choice

What is the monomeric unit of neoprene?

  1. 2-chloro-1, 3-butadiene

  2. 1, 3-butadiene

  3. 2-methyl-1, 3-butadiene

  4. 3-methyl-1, 3-pentadiene

  5. None of the above
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

It is the monomer unit of natural rubber which is also called polyisoprene.

Multiple choice

Which of the following sets represents the meta-directing functional groups?

  1. -OH, -NR2, -CH3

  2. -NO, -SO3H, -CHO

  3. -NO2, -CN, -NR2

  4. -NO, -SO3H, -NR2

  5. -OH, -NR2, -SO3H
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

A monosubstituted benzene, when treated with an electrophile, undergoes electrophilic aromatic substitution reactions. Each reaction yields a disubstituted benzene as the organic product, which can be identified using the descriptors ortho, para and meta products. Common ortho and para directing groups are: -OH, -NR2, -CH3, -NR2 etc. Common meta directing groups are: -NO, -SO3H, -CHO, -NO2, -CN etc.

Multiple choice

Which among the following species is/are ortho and para directing group?

  1. –COCH3
  2. –SO3H
  3. –NR3+
  4. –OCH3

  1. Only 2

  2. Only 3

  3. Only 4

  4. 1 and 3

  5. 3 and 4
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Monosubstituted benzene when treated with an electrophile, undergoes electrophilic aromatic substitution reactions. Each reaction yields disubstituted benzene as the product, which can be identified using the descriptors ortho, para and meta as products. Common ortho and para directing groups are: -OH, -OCH3, -NR2, -CH3, -NR2 etc. Common meta directing groups are: -NO, -SO3H, -COCH3, -CHO, -NO2, -CN, -NR3+ etc. Hence, only –OCH3 group is ortho and para directing.

Multiple choice

C6H6 is

  1. benzene

  2. methane

  3. ethane

  4. None of these
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

C6H6 is the molecular formula of benzene.

Multiple choice

Which of the following pairs possess V-shaped geometry?

  1. SnCl2, SeH2

  2. SO2, CO2

  3. H2O, ClO-

  4. ICl, ClO-

  5. SCl2, XeF2
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

SnCl2 has one lone pair of electrons with V-shaped geometry. SeH2 has two lone pairs of electrons with V-shaped geometry. SO2 has one lone pair of electrons with V-shaped geometry while CO2 has zero lone pair of electrons with linear shape.