What is the percentage by mass of carbon in methane, CH₄ (C = 12, H = 1)?
Correct answer C. 75%
Topic / 36 questions
Fundamental Principles of Organic Chemistry MCQs
Fundamental Principles of Organic Chemistry MCQs are multiple-choice questions on the definition and classification of organic compounds, functional groups, homologous series and isomerism, including stereoisomerism. They follow the MDCAT chemistry curriculum, and every question on MCQs360 shows its correct answer instantly so you can build a strong base for the organic units that follow.
- Gases 40
- Liquids 40
- Solids 40
- Chemical Equilibrium 40
- Reaction Kinetics 40
- Thermochemistry and Energetics 40
- Electrochemistry 40
- Fundamental Concepts of Chemistry 40
- Atomic Structure 39
- Chemical Bonding 39
- Alcohols and Phenols 38
- Industrial Chemistry 37
- Aldehydes and Ketones 37
- Alkyl Halides 37
- s- and p-Block Elements 37
- Chemistry of Hydrocarbons 36
- Fundamental Principles of Organic Chemistry 36
- Carboxylic Acids 36
- Transition Elements 35
- Macromolecules 35
What is the maximum number of stereoisomers for a compound with three different chiral carbon atoms?
Correct answer A. 8
Which of these alcohols is optically active?
Correct answer A. Butan-2-ol
Advertisement
Which of these compounds can show geometric (cis-trans) isomerism?
Correct answer C. But-2-ene
Diethyl ether and methyl propyl ether show which type of isomerism?
Correct answer A. Metamerism
Ethanol and dimethyl ether are an example of which type of isomerism?
Correct answer B. Functional group isomerism
The functional group −COOR is characteristic of which class of compounds?
Correct answer B. Esters
What is the name of the functional group present in CH₃CONH₂?
Correct answer D. Amide
Open-chain organic compounds are also known as ____ compounds.
Correct answer C. acyclic
Advertisement
Which of these compounds is usually NOT classified as an organic compound?
Correct answer D. Calcium carbonate
Which of these is a heterocyclic compound?
Correct answer C. Pyridine
How many isomeric dichlorobenzenes, C₆H₄Cl₂, are possible?
Correct answer B. 3
What is the degree of unsaturation (double bond equivalent) of benzene, C₆H₆?
Correct answer B. 4
Successive members of a homologous series differ in molar mass by ____.
Correct answer B. 14 g mol⁻¹
How many σ and π bonds are present in acrylonitrile, CH₂=CH–C≡N?
Correct answer B. 6 σ and 3 π
Advertisement
A racemic mixture is optically inactive because ____.
Correct answer C. equal amounts of two enantiomers cancel each other's rotations
Which property is greater for cis-but-2-ene than for trans-but-2-ene?
Correct answer B. Dipole moment
Two enantiomers of the same compound differ in ____.
Correct answer B. the direction in which they rotate plane-polarised light
Ethanol (C₂H₅OH) and methoxymethane (CH₃OCH₃) are an example of ____ isomerism.
Correct answer D. functional group
Modern organic chemistry is best defined as the chemistry of ____.
Correct answer B. hydrocarbons and their derivatives
About Fundamental Principles of Organic Chemistry MCQs
The opening questions cover what organic chemistry studies and how compounds are classified into open-chain (acyclic) and closed-chain (cyclic) types, with cyclic compounds divided into homocyclic and heterocyclic groups such as pyridine. You will need to recognise functional groups such as ketones, esters, amides and carboxylic acids and know the features of a homologous series. Isomerism questions ask you to count structural isomers of alkanes such as C₅H₁₂ and C₆H₁₄, identify chain, position and functional group isomers, decide which alkenes show cis-trans isomerism and explain optical activity and racemic mixtures. Some questions also test sigma and pi bond counts and the degree of unsaturation.
Key facts to remember
- Organic chemistry is the chemistry of carbon compounds, mainly hydrocarbons and their derivatives.
- Successive members of a homologous series differ by a CH₂ unit, or 14 g mol⁻¹ in molar mass.
- C₄H₁₀ has 2 structural isomers, C₅H₁₂ has 3 and C₆H₁₄ has 5.
- Ethanol (C₂H₅OH) and methoxymethane (CH₃OCH₃) are functional group isomers.
- Cis-trans isomerism needs restricted rotation, as around a C=C bond, and two different groups on each carbon of the double bond.
- A racemic mixture contains equal amounts of two enantiomers, so it is optically inactive by external compensation.
Exams that include Fundamental Principles of Organic Chemistry MCQs
Pakistan
- MDCAT
- ECAT
- NUMS
- AKU
- FSc boards
India
- NEET
- JEE Main
Bangladesh
- HSC
- Medical Admission Test
How to prepare for Fundamental Principles of Organic Chemistry MCQs
- Make flashcards of functional groups with their general formula, suffix or prefix and one example.
- Practise drawing all isomers of C₄H₁₀, C₅H₁₂ and C₆H₁₄ systematically by shortening the main chain.
- For cis-trans questions, check that each double-bonded carbon carries two different groups.
- Learn the degree of unsaturation formula and check it with benzene, which has a value of 4.
Frequently asked questions
What does the MDCAT syllabus include in Fundamental Principles of Organic Chemistry?
The PMDC MDCAT curriculum covers the definition of organic chemistry and the structural classification of organic compounds, the main functional groups, and isomerism, including structural isomerism and stereoisomerism. These ideas are used throughout the later organic units, so this topic is worth revising thoroughly.
Which exams ask organic chemistry basics MCQs?
Questions on classification, functional groups and isomerism appear in MDCAT, ECAT, NUMS and AKU entry tests and FSc board papers in Pakistan. They also feature in NEET and JEE Main in India and in HSC and medical admission tests in Bangladesh.
What is a heterocyclic compound?
A heterocyclic compound has a ring that contains at least one atom other than carbon, such as nitrogen, oxygen or sulphur. Pyridine, C₅H₅N, and furan are common examples, while benzene and cyclohexane are homocyclic because their rings contain only carbon.
Last reviewed October 2026