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NEET GOC (basic principles of organic chemistry): 5 practice MCQs

By the PrepMatic team · Updated 9 Oct 2026 · 3 min read

GOC, or General Organic Chemistry, is the foundation of the whole organic section of NEET Chemistry. If you understand electron effects, intermediates and nomenclature here, every later reaction becomes easier to follow. The five MCQs below test IUPAC naming, carbocation stability, nucleophiles, counting isomers and the inductive effect on acid strength.

What this chapter covers in the NEET syllabus

The NMC unit is Some Basic Principles of Organic Chemistry, the NCERT Class 11 chapter often called GOC. Purification and characterisation of organic compounds is a separate NMC unit. The GOC topics are:

• Tetravalency of carbon, hybridisation, shapes of simple molecules and classification of organic compounds by functional group.
• Homologous series, and IUPAC nomenclature (with trivial names).
• Isomerism: structural and stereoisomerism.
• Bond fission: homolytic and heterolytic, giving free radicals, carbocations and carbanions; electrophiles and nucleophiles.
• Electronic effects: inductive, electromeric, resonance and hyperconjugation.
• Types of organic reactions: substitution, addition, elimination and rearrangement.

Five practice MCQs on GOC

Question 1

The IUPAC name of the compound CH₃CH(CH₃)CH₂CH₃ is:

• A. 3-methylbutane
• B. 2-methylbutane
• C. 2-ethylpropane
• D. 1,1-dimethylpropane

Question 2

Which of the following carbocations is the most stable?

• A. CH₃⁺
• B. CH₃CH₂⁺
• C. (CH₃)₂CH⁺
• D. (CH₃)₃C⁺

Question 3

Which of the following is a nucleophile?

• A. NH₃
• B. BF₃
• C. AlCl₃
• D. NO₂⁺

Question 4

The number of structural isomers of C₅H₁₂ is:

• A. 2
• B. 4
• C. 3
• D. 5

Question 5

Which of the following is the strongest acid?

• A. CH₃COOH
• B. ClCH₂COOH
• C. Cl₂CHCOOH
• D. Cl₃CCOOH

Answers and explanations

1. B. The longest chain has four carbons (butane), and the methyl group is on carbon 2 when numbering from the end that gives the lower number. So the name is 2-methylbutane. In option A, numbering is wrong, since the substituent would get position 3 instead of 2.
2. D. A tertiary carbocation has three alkyl groups donating electrons by the +I effect and by hyperconjugation (nine C-H bonds), so the positive charge is most dispersed. Stability falls in the order tertiary, secondary, primary, methyl.
3. A. A nucleophile donates a pair of electrons, and NH₃ has a lone pair on nitrogen. BF₃ and AlCl₃ are electron-deficient (Lewis acids) and NO₂⁺ is an electrophile.
4. C. C₅H₁₂ has three structural isomers: n-pentane, 2-methylbutane (isopentane) and 2,2-dimethylpropane (neopentane). Drawing the chains systematically from the longest to the most branched avoids repeats.
5. D. Chlorine is electron withdrawing (the −I effect). The more chlorine atoms on the carbon next to the carboxyl group, the more the carboxylate anion is stabilised, so the acid is stronger. Trichloroacetic acid is the strongest of the four.

How to prepare GOC

• Treat GOC as a set of tools, not facts. Learn what each electronic effect does: +I and −I (through sigma bonds, decreasing with distance), resonance (+M and −M, through pi bonds) and hyperconjugation (sigma bonds next to a pi bond or a positive centre).
• Practise stability orders until they are automatic. Carbocations (tertiary is more stable than secondary, then primary, and allyl and benzyl are extra stable), free radicals (same order), carbanions (the reverse order) and the acid strength of substituted benzoic acids and phenols.
• Name compounds in a fixed sequence. Find the principal functional group, choose the longest chain containing it, number to give it the lowest locant, then add substituents alphabetically. Practise 20 names, including those with double bonds and more than one substituent.
• Count isomers systematically. For structural isomers, vary chain length, branching, position of the group and functional group in that order. For stereoisomers, look for a double bond with two different groups on each carbon and for chiral centres.
• Link to reaction types. Know which species reacts with which: electrophiles attack electron-rich sites such as double bonds, and nucleophiles attack electron-poor carbons.

GOC pays back across the entire organic section, so give it a full week with daily practice. The NEET organic chemistry guide shows how to build on it, and the NEET Chemistry preparation guide shows where organic fits in the plan.

Take a full GOC test on PrepMatic

Organic chemistry builds on GOC, so test it before moving on. A PrepMatic topic test is about 15 questions in 30 minutes and is scored with NEET's negative marking. The free Basic plan includes topic tests, and Hydrocarbons is the natural next chapter.

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