Free Fundamental Principles of Organic Chemistry MCQs with Answers
536 Fundamental Principles of Organic Chemistry MCQs from Chemistry, each with the correct answer and a written explanation of why it is correct. Free and unlimited, with no account needed.
Organic chemistry begins with carbon compounds classified by carbon skeleton, saturation and functional group. Work includes identifying groups such as hydroxyl, carbonyl, carboxyl and amino, applying basic nomenclature, and distinguishing structural, geometric and optical isomers, where the same molecular formula does not necessarily mean the same structure or properties.
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Read the Fundamental Principles of Organic Chemistry notesFree MDCAT chapter notes with key terms536 questions · page 9 of 27
- A. - al
- B. - oic
- C. - ol
- D. - ene
Explanation: In IUPAC nomenclature, the suffix used to denote the carboxylic acid functional group (-COOH) is "-oic acid".
Correct answer: - oic- A. R3C+
- B. CH3+
- C. R2CH+
- D. RCH2+
Explanation: The stability of carbocations is increased by electron-donating groups, such as alkyl groups, through inductive effects and…
Correct answer: CH3+- A. CnH2n+2
- B. CnH2n-2
- C. CnH2n+1
- D. CnH2n-1
Explanation: Alkanes have the general formula CnH2n+2. Removing one hydrogen atom results in a species called an alkyl group, which has the general…
Correct answer: CnH2n+1- A. High boiling points
- B. High melting points
- C. Low melting points
- D. Low vapor pressure
Explanation: Melting and boiling points are a measure of the energy required to overcome intermolecular forces.
Correct answer: Low melting points- A. Chain isomerism
- B. Metamerism
- C. Tautomerism
- D. Position isomerism
Explanation: Metamerism is a type of isomerism where compounds have the same molecular formula and the same functional group, but differ in the nature…
Correct answer: Metamerism- A. Ionic bond
- B. Covalent bond
- C. Hydrogen bond
- D. Metallic bond
Explanation: Carbon has four valence electrons and a moderate electronegativity. It achieves a stable octet by sharing electrons with other atoms…
Correct answer: Covalent bond- A. Heterocyclic
- B. Hydrocarbon
- C. Alicyclic
- D. Homocyclic
Explanation: Pyridine is an aromatic compound with a six-membered ring similar to benzene.
Correct answer: Heterocyclic- A. Asymmetry
- B. Rotation around a single bond
- C. Resonance
- D. Restricted rotation around a double bond
Explanation: The presence of a pi bond in a carbon-carbon double bond prevents free rotation around the bond axis.
Correct answer: Restricted rotation around a double bond- A. Lewis
- B. Wohler
- C. Berzelius
- D. Democritus
Explanation: In 1828, Friedrich Wohler synthesized urea from the inorganic compound ammonium cyanate.
Correct answer: Wohler- A. Reforming
- B. Cracking
- C. Annealing
- D. Pickling
Explanation: The process of converting straight-chain alkanes into their branched-chain isomers is specifically called isomerization.
Correct answer: Reforming- A. High molecular mass
- B. Low molecular mass
- C. Low boiling point
- D. Both B and C
Explanation: Natural gas is primarily composed of methane (CH₂), along with smaller amounts of other light alkanes like ethane and propane.
Correct answer: Both B and C172. Carbon is:
- A. Trivalent
- B. Tetravalent
- C. Monovalent
- D. Pentavalent
Explanation: Carbon has four valence electrons and typically forms four covalent bonds to achieve a stable octet.
Correct answer: Tetravalent- A. Metamerism
- B. Chain isomerism
- C. Tautomerism
- D. Functional group isomerism
Explanation: These two compounds share the same molecular formula (C₂H6O) but have different functional groups.
Correct answer: Functional group isomerism- A. CH3CONCH3
- B. NH2CONH2
- C. NH4CNO
- D. NH4CHO
Explanation: The formula is constructed from its constituent ions: the ammonium ion is NH4+and the cyanate ion is CNO-.
Correct answer: NH4CNO- A. Lime kiln
- B. Domestic purposes
- C. Fuel
- D. Motor bikes
Explanation: While coal has many uses, in some regions with specific industrial profiles, a significant portion (sometimes up to 80%) of the locally…
Correct answer: Lime kiln- A. Alkanes
- B. Alkenes
- C. Alkynes
- D. All of these
Explanation: Alkanes are the class of saturated hydrocarbons. By definition, they contain only single covalent bonds between their carbon atoms.
Correct answer: Alkanes177. Which of the following conditions must be possessed by a compound to have geometrical isomerism?
- A. Double bond
- B. Different groups attach to same carbon of double bond
- C. Same groups attach to carbon atom of double bond
- D. Both A and B
Explanation: To exhibit geometric (cis-trans) isomerism, a molecule must have restricted rotation (usually from a double bond or ring) and each of the…
Correct answer: Both A and B- A. High electronegativity
- B. Ability to form four covalent bonds
- C. Presence in all living organisms
- D. Low atomic mass
Explanation: Carbon has four valence electrons, allowing it to form four stable covalent bonds with other atoms. leading to diverse organic compounds.
Correct answer: Ability to form four covalent bonds- A. sp
- B. sp2
- C. sp3
- D. sp3d
Explanation: In ethene, each carbon forms three sigma bonds and one pi bond, which corresponds to sp2 hybridization.
Correct answer: sp2- A. CnH2n+2
- B. CnH2n
- C. CnH2n-2
- D. CnHn
Explanation: Alkanes are saturated hydrocarbons with single bonds, and their general formula is CnH2n+2.
Correct answer: CnH2n+2