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

Assertion: CHBr=CHCl exhibits geometrical isomerism but CH2Br-CH2Cl does not. Reason: Presence of C=C is one of the conditions of geometrical isomerism.

  1. Both A and R are true and R is the correct explanation of A.

  2. Both A and R are true but R is NOT the correct explanation of A.

  3. A is true but R is false.

  4. A is false but R is true.

  5. Both A and R are false.
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

CHBr=CHCl exhibits geometrical isomerism but CH2Br-CH2Cl does not, because the molecule may or may not contain a double bond, only restricted rotation about a bond give rise to geometrical isomerism. Thus, this option is correct.

Multiple choice

Match the following according to which the nomenclature of organic compounds is done ||||| |---|---|---|---| |1|Prefix|a|Number of carbon atoms| |2|Root word|b|Nature of bond| |3|Suffix|c|Functional group|

  1. 1 - a, 2 - b, 3 - c

  2. 1 - c, 2 - b, 3 - a

  3. 1 - b, 2 - a, 3 - c

  4. 1 - b, 2 - c, 3 - a

  5. 1 - a, 2 - c, 3 - b
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Yes, it is correct. Prefix is the Number of carbon atoms. Root word is the nature of bond i.e. double or single bond and suffix is the functional group attached.

Multiple choice

Which is the formula of chloroform?

  1. CH2Cl

  2. CHCl3

  3. CHCl5

  4. CO2
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Chloroform has the chemical formula CHCl3, containing one carbon, one hydrogen, and three chlorine atoms. CH2Cl is incomplete, CHCl5 is chemically impossible (carbon can only form 4 bonds), and CO2 is carbon dioxide.

Multiple choice

Assertion: Azulene is a non-benzenoid compound. Reason: It is planar, has a cyclic array of 10 π-electrons but does not contain benzene rings.

  1. Both A and R are true and R is the correct explanation of A.

  2. Both A and R are true but R is NOT the correct explanation of A.

  3. A is true but R is false.

  4. A is false but R is true.

  5. Both A and R are false.
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

This option is correct because azulene is a non-bezenoid aromatic compound and it contains 5 π-bonds or 10 π-electrons but does not contain benzene rings.

Multiple choice

Assertion: Cyclooctatetraene reacts with two equivalents of potassium to form a stable compound with formula 2K+ C8H82-. Reason: Cyclooctatetraene is non-aromatic but 2K+ C8H82- is aromatic.

  1. Both A and R are true and R is the correct explanation of A.

  2. Both A and R are true but R is NOT the correct explanation of A.

  3. A is true but R is false.

  4. A is false but R is true.

  5. Both A and R are false.
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

This option is correct,  because Cyclooctatetraene reacts with two equivalents of potassium to form a stable compound with formula 2K+ C8H82- and 2K+ C8H82- is aromatic.

Multiple choice

Two hexoses were found to give the same osazone. Which one of the following statements is correct with respect to their structural relationship? A. The carbon atoms 1 and 2 in both have the same configuration. B. They are epimeric at C3. C. The carbon atoms 3, 4 and 5 in both have the same configuration.

  1. Only A

  2. Only B

  3. Only C

  4. Both A and B

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

This option is correct,  because osazone formation involves reactions at C1 and C2, therefore, if two hexoses form the same osazone, they must have the same configuration at C3, C4 and C5.

Multiple choice

The isomerism exhibited by C2H5-O-C2H5 and CH3-O-CH(CH3)2 is

  1. functional

  2. metamerism

  3. position

  4. chain

Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Both compounds are ethers with molecular formula C4H10O. Diethyl ether (C2H5-O-C2H5) and methyl isopropyl ether (CH3-O-CH(CH3)2) differ only in the alkyl groups attached to the oxygen atom. This is metamerism - a type of structural isomerism where the functional group remains the same but the alkyl groups on either side vary.

Multiple choice

Which of the following statements is not correct about trans-C2H2Cl2?

  1. It has one C2 symmetry element.

  2. Structure of this molecule is non planar.

  3. Two chlorine atoms are opposite to each other.

  4. It has one horizontal plane.

  5. Point group of this molecule is C2h.
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Correct option. Trans-C2H2Cl2 molecule is planar due to sp2 hybridisation.

Multiple choice

Which of the following is true about the structure of C2H2 molecule?

  1. Infinite number of vertical planes

  2. Infinite number of horizontal planes

  3. Non-linear structure

  4. C4 principal axis of rotation

  5. Two horizontal planes of symmetry
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Correct option. C2H2 is a symmetrical linear molecule. So, infinite number of vertical planes are there.