Class 11 Chemistry

1. What is the general formula of open-chain alkanes?

• A. CₙH₂ₙ₊₂
• B. CₙH₂ₙ
• C. CₙH₂ₙ₋₂
• D. CₙH₂ₙ₋₆

2. Wurtz reaction involves heating an alkyl halide with sodium metal in dry ether to form:

• A. Higher alkane containing even number of carbon atoms
• B. Alkenes
• C. Alkynes
• D. Alcohols

3. Which of the following alkanes cannot be prepared in good yield by Wurtz reaction?

• A. Methane (CH₄)
• B. Ethane (C₂H₆)
• C. n-Butane (C₄H₁₀)
• D. n-Hexane (C₆H₁₄)

4. Heating sodium ethanoate (CH₃COONa) with soda lime (NaOH + CaO) produces:

• A. Methane
• B. Ethane
• C. Propane
• D. Ethene

5. According to Markovnikov's rule, addition of unsymmetrical reagent (like HBr) to unsymmetrical alkene adds the negative part to:

• A. Carbon atom with fewer hydrogen atoms
• B. Carbon atom with more hydrogen atoms
• C. Any carbon atom randomly
• D. Oxygen atom

6. Anti-Markovnikov addition of HBr to alkenes occurs in the presence of:

• A. Organic Peroxides
• B. Anhydrous AlCl₃
• C. Concentrated H₂SO₄
• D. Nickel catalyst

7. Ozonolysis of ethene followed by reduction with Zn/H₂O yields:

• A. Methanal (Formaldehyde)
• B. Ethanal (Acetaldehyde)
• C. Methanol
• D. Formic acid

8. What is the geometry around double-bonded carbon atoms in alkenes?

• A. Trigonal planar
• B. Tetrahedral
• C. Linear
• D. Octahedral

9. Which of the following hydro-carbons displays acidic hydrogens capable of reacting with sodium metal?

• A. Ethyne (Acetylene)
• B. Ethane
• C. Ethene
• D. Benzene

10. Cyclic polymerization of ethyne (C₂H₂) by passing through a red-hot iron tube at 873 K forms:

• A. Benzene
• B. Cyclohexane
• C. Toluene
• D. Cyclooctatetraene

11. According to Huckel's rule, a planar monocyclic conjugated ring system is aromatic if it contains:

• A. (4n + 2) π electrons
• B. 4n π electrons
• C. (2n + 2) π electrons
• D. (n + 2) π electrons

12. Benzene reacts with CH₃Cl in the presence of anhydrous AlCl₃ to form toluene. This reaction is known as:

• A. Friedel-Crafts Alkylation
• B. Friedel-Crafts Acylation
• C. Wurtz-Fittig Reaction
• D. Reimer-Tiemann Reaction

13. What catalyst is used in Nitration of Benzene alongside concentrated HNO₃?

• A. Concentrated H₂SO₄
• B. Anhydrous AlCl₃
• C. FeCl₃
• D. Pt catalyst

14. Which functional group is ortho- and para-directing in aromatic electrophilic substitution?

• A. -OH group
• B. -NO₂ group
• C. -COOH group
• D. -CHO group

15. Which substituent is strongly meta-directing and deactivating on a benzene ring?

• A. -NO₂
• B. -CH₃
• C. -NH₂
• D. -OCH₃

16. Conformations of ethane which have maximum and minimum potential energy are respectively:

• A. Eclipsed and Staggered
• B. Staggered and Eclipsed
• C. Skew and Eclipsed
• D. Chair and Boat

17. Addition of water to ethyne in the presence of H₂SO₄ and HgSO₄ at 333 K yields:

• A. Ethanal (Acetaldehyde)
• B. Ethanol
• C. Methanal
• D. Ethanoic acid

18. Lindlar's catalyst used for partial hydrogenation of alkynes to cis-alkenes is:

• A. Palladised charcoal deactivated with BaSO₄ or quinoline
• B. Sodium in liquid ammonia
• C. Raney Nickel
• D. Pt in acidic medium

19. Reduction of alkynes with Sodium in liquid Ammonia (Birch reduction) produces:

• A. trans-Alkenes
• B. cis-Alkenes
• C. Alkanes
• D. Aromatic compounds

20. Ozonolysis of propene followed by Zn/H₂O gives:

• A. Ethanal and Methanal
• B. Two molecules of Ethanal
• C. Propanone and Methanal
• D. Propanal and Water

21. The chemical test used to distinguish between alkanes and alkenes is:

• A. Bromine water test
• B. Tollen's test
• C. Fehling's test
• D. Biuret test

22. What product is formed when Benzene is treated with excess Cl₂ in presence of anhydrous AlCl₃ in dark?

• A. Hexachlorobenzene (C₆Cl₆)
• B. Benzene hexachloride (BHC)
• C. Chlorobenzene
• D. Dichlorobenzene

23. Gammaxane (Lindane) is chemically known as:

• A. Benzene hexachloride (1,2,3,4,5,6-hexachlorocyclohexane)
• B. Hexachlorobenzene
• C. Chlorobenzene
• D. DDT

24. What is the major product of Dehydrohalogenation of 2-bromobutane with alcoholic KOH?

• A. But-2-ene
• B. But-1-ene
• C. Butan-2-ol
• D. Butane

25. Kolbe's electrolytic method of sodium acetate solution yields which gas at the anode?

• A. Ethane and CO₂
• B. Methane and O₂
• C. Hydrogen only
• D. Ethene and CO

26. Which conformer of cyclohexane is the most stable?

• A. Chair form
• B. Boat form
• C. Twist-boat form
• D. Half-chair form

27. What is the number of sigma (σ) and pi (π) bonds present in a Benzene molecule?

• A. 12 σ and 3 π
• B. 6 σ and 3 π
• C. 9 σ and 3 π
• D. 12 σ and 6 π

28. Which gas is liberated when calcium carbide (CaC₂) reacts with water?

• A. Ethyne
• B. Ethene
• C. Methane
• D. Ethane

29. Complete combustion of any hydrocarbon produces:

• A. CO₂ and H₂O
• B. CO and H₂
• C. Carbon black and H₂O
• D. CH₄ and O₂

30. Friedel-Crafts Acylation of benzene with acetyl chloride (CH₃COCl) in presence of AlCl₃ forms:

• A. Acetophenone
• B. Toluene
• C. Benzoic acid
• D. Chlorobenzene