General Organic Chemistry is an important chapter in JEE Main Chemistry Syllabus. About 33% of the questions in JEE Main exam are from Organic Chemistry topics. Students can expect 6-8 questions from Organic Chemistry and its subtopics with a weightage of about 25-35 marks in JEE Main 2021 paper. 

Having a strong and accurate understanding of the concepts is important in preparing for advanced topics. Some of the important topics in JEE Main Organic Chemistry chapter includes Purification and Characterisation of Organic Compounds, Basic Principles of Organic Chemistry, Hydrocarbons, Organic Compounds Containing Halogens, Organic Compounds Containing Oxygen and Nitrogen, Polymers, Biomolecules, etc. Check JEE Main Chemistry Syllabus

Chemistry is often considered the easiest section in JEE Main Question Paper, however, organic chemistry questions can be a bit tricky and difficult as compared to other topics. Based on previous year paper analysis, students found NCERT Chemistry Book to be the best source of chemistry preparation for JEE Main as most questions were based on NCERT exercises.

General Organic Chemistry Previous Year Questions with Solutions will help candidates in getting a better understanding of the type of questions asked and the difficulty level of the exam. Given below are a few previous year questions with solutions on JEE Main General Organic Chemistry, allowing candidates to ace up their preparation.

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JEE Main Organic Chemistry Questions and Solutions

Last year’s papers questions with solutions will be useful in getting a detailed understanding of the style of questions that can come in the exam and the students can prepare accordingly for the same.

Question. What will be the arrangement of (CH3)3– C-, (CH3)-CH-, CH3– CH2-, when attached to benzyl or an unsaturated group, in increasing order of inductive effect? (2002)

1. (CH3)3-C – < (CH3)2 – CH – < CH3 – CH2
2. CH3-CH2 – < (CH3)2 – < CH – < (CH3)3-C –
3. (CH3)2 – CH < (CH3)3 – C -< CH3 – CH2
4. (CH3)3 – C -< CH3 – CH2 < (CH3)2 – < CH

Solution. The correct option is 2. CH3 group has + I effect, as number of -CH3 group increases, the inductive effect will also increase.

Question. Name the most basic compound among the ones mentioned below (2005)

• Acetanilide
• Benzylamine
• p-Nitro aniline
• Aniline
• Solution:

Solution. Benzylamine is more basic. So the correct option is 2. 

Question. Due to the presence of an unpaired electron, free radicals include (2005)

1. Chemically reactive
2. Chemically inactive
3. Anions 
4. Cations

Solution. The correct option is 1. Free radicals are chemically active.

Question. Looking at the basic strength of amines in aqueous solution, which of the following has the smallest pKb value? (2002)

1. (CH3)3N
2. C6H5NH2
3. (CH3)2NH
4. CH3NH2

Solution. Due to the steric effect, a slight discrepancy occurs in case of trimethyl amine. So (CH3)2NH has the smallest pKb value. So the correct option would be 3.

Question. Name the molecule that have the lowest dipole moment out of the ones mentioned below:-

1. CHCl3
2. CH2Cl2
3. CCl4
4. CH3Cl

Solution. Dipole moment of CCl4 is 0. So the accurate answer is 3.

Question. Name the compounds, which are not soluble in sodium bicarbonate ?

1. Benzene sulphonic acid
2. Benzoic acid
3. o-Nitrophenol
4. 2, 4, 6 – Trinitrophenol

Solution. Since Trinitrophenol is higher in acidity so it will not sodium bicarbonate. Hence the accurate answer is 3.

Question. Name the compound that will be formed in the positive test for nitrogen with the Lassaigne solution of an organic compound? (2004)

1. Fe4[Fe(CN)6]3
2. Na4[Fe(CN)5NOS]
3. Fe(CN)3
4. Na3[Fe(CN)6]

Solution. The compound which is formed in the positive test for nitrogen with the Lassaigne solution of an organic compound is prussian blue coloured complex compound ferric ferrocyanide. So the accurate option is 1.

Question. What will be the general formula of CnH2n02 in the open chain (2003)

1. carboxylic acids
2. diols
3. dialdehydes
4. diketones

Solution. The general formula CnH2n02 could be for open chain carboxylic acid or ester. So the correct reply to this questions is 1.

Question. What will be the correct decreasing order of acid strength in the beneath oxoacids?

1. HClO4 > HClO3 > HClO2 > HOCl
2. HClO2 > HClO4 > HClO3 > HOCl
3. HOCl > HClO2 > HClO3 > HClO4
4. HClO4 > HOCl > HClO2 > HClO3

Answer. Acidic strength is directly proportional to the oxidation number. Its increasing acid strength is due to an increase in the oxidation state of the central atom. So the accurate reply would be 1.

Question. Ortho-Nitrophenol is less soluble in water than p– and m– Nitrophenols because:

1. Melting point of o–Nitrophenol is lower than those of m– and p– isomers
2. o–Nitrophenol is more volatile in steam than those of m– and p– isomers
3. o–Nitrophenol shows Intramolecular H–bonding
4. o–Nitrophenol shows Intermolecular H–bonding

Answer. Intramolecular H-bonding is present in o-nitrophenol. So solubility in water is decreased.

Hence option (3) is the answer.

Question. What will be the order of basicity of amines in gaseous state? (2004)

1. 30 > 20 > NH3 > 10
2. 10 > 20 > 30 > NH3
3. NH3> 10 > 20 > 30
4. 30 > 20 > 10 > NH3

Solution: The basicity is proportional to +I effect. The correct option would be 4.

Question. Which one of the beneath conformation of cyclohexane is chiral?

1. Twist boat
2. Rigid
3. Chair
4. Boat

Solution: Twist boat is chiral because it doesn't have any plane of symmetry. So we can conclude that the accurate option is 1.

Question. Increasing order of stability among the three main conformations (i.e. Eclipse, Anti, Gauche) of 2-fluoroethanol is

1. Eclipse, Gauche, Anti
2. Gauche, Eclipse, Anti
3. Eclipse, Anti, Gauche
4. Anti, Gauche, Eclipse

Solution: Eclipse is the lowest stable while Gauche’s stability is maximum. So candidates here need to tick on the 3rd option as it is correct.

Question. Name the one that does not have sp2 hybridized carbon?

1. Acetone
2. Acetamide
3. Acetonitrile
4. Acetic acid

Solution: Acetonitrile has only sp3 and sp hybridized carbon atoms. So it will be the correct option. 

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JEE Main General Organic Chemistry Quick Formulas

Organic Chemistry is a subdivision of Chemistry that deals with carbon compounds. Learning formulas is important for all the JEE aspirants as it helps them solve the questions quickly. Some of the formulas that are important for you to learn in general organic chemistry include:

Formula Set 1

Formula Set 2

Formula Set 3

Formula Set 4

• Positive Electromeric Effect: p-electrons transfer takes place C to C (as alkenes, alkynes etc.)

• Negative Electromeric Effect: p-electrons transfer takes place to more electronegative atom (O,N,S) that are connected by several bonds.

Some other important formulas include:

1. Estimation of closest distance of approach (derivation) of α -particle:

R = \frac{4KZe^{2}}{m_{\alpha }V_{\alpha }^{2}}R=mαVα24KZe2

2. The radius of a nucleus:

\quad R = R _{0}( A )^{1/3} cmR=R0(A)1/3cm

3. Planck’s Quantum Theory: 

Energy\: of\: one\: photon = h v=\frac{ hc }{\lambda}Energyofonephoton=hv=λhc

4. Photoelectric Effect: 

hv =h v_{0}+\frac{1}{2} m_{e} v^{2}hv=hv0+21mev2

5. Bohr’s Model for Hydrogen like atoms:

mvr = n \frac{ h }{2 \pi}\: (Quantization\: of\: angular\: momentum)mvr=n2πh(Quantizationofangularmomentum)

E _{ n }=-\frac{ E _{1}}{ n ^{2}} z ^{2}=2.178 \times 10^{-18} \frac{ z ^{2}}{ n ^{2}} J / atom =13.6 \frac{ z ^{2}}{ n ^{2}} eV ; \quad E _{1}=\frac{-2 \pi^{2} me ^{4}}{ n ^{2}}En=−n2E1z2=2.178×10−18n2z2J/atom=13.6n2z2eV;E1=n2−2π2me4

r_{n}=\frac{n^{2}}{z} \times \frac{n^{2}}{4 \pi^{2} e^{2} m}=\frac{0.529 \times n^{2}}{z} Arn=zn2×4π2e2mn2=z0.529×n2A

v=\frac{2 \pi ze ^{2}}{ nh }=\frac{2.18 \times 10^{6} \times z }{ n } m / sv=nh2πze2=n2.18×106×zm/s

6. De-Broglie wavelength: 

\lambda=\frac{ h }{ mc }=\frac{ h }{ p }(\text { for photon })λ=mch=ph( for photon )

General Organic Chemistry includes all the fundamental concepts in huge organic chemistry. In case you have a strong understanding of all the concepts that come under GOC plays, you can get a good score ahead.

Above mentioned are some of the important formulae that help you crack JEE Main Chemistry section. The best way to remember the formulas is to revise often. Apart from that, you must also practice solving problems often, the more you practice and use the equations, the better ways to solve the questions in the JEE exam will be explored by you.

Also Check JEE Main 2021 Sample Papers