Class 11 Chemistry — Chapter 13: Hydrocarbons Online Test

1. The term "polynuclear" in refers to the presence of:

2. The primary reason the Methyl group () is an activating and -directing group is its ability to donate electrons via:

3. When the product of a Friedel–Crafts acylation () is treated with and concentrated (Clemmensen Reduction), the final product obtained is a:

4. The final step in the halogenation mechanism is the regeneration of the catalyst and the aromatic ring. This involves the removal of which species from the complex?

5. In the reaction , the bond of the benzene ring is broken, and a new bond is formed. This step is a characteristic of:

6. The overall nitration reaction is written as: . How is this reaction classified in terms of heat change?

7. The initial slow step in the mechanism of benzene nitration involves the attack of the electrophile on the benzene ring to form:

8. The addition of water () to Ethyne () in the presence of and yields an intermediate enol, which quickly tautomerizes to form the final product:

9. After an alkyne salt () is formed using , how is the neutral terminal alkyne () typically regenerated?

10. Starting with 1,1-Dichloropropane and performing double dehydrohalogenation, what is the final alkyne product?

11. The carbon atoms involved in the triple bond of an alkyne are linked by which combination of bonds?

12. Ozonolysis of an unknown alkene yields () and (). Identify the structure of the starting alkene.

13. Halogenation of an alkene with or results in the formation of which type of product?

14. The conversion of a vicinal dihalide () to an alkene requires treatment with:

15. The compound 2,3-Dimethylbut-2-ene does not show geometrical isomerism because:

16. The two carbon atoms involved in the double bond of an alkene are linked by which combination of bonds?

17. Decarboxylation is considered a useful method for:

18. What is the molecular formula for -Hexane?

19. What is the approximate bond length in a typical alkyne, such as Ethyne ()?

20. How many sigma () and pi () bonds are present in Propene ()?

1. Which catalyst system is typically used in the industrial production of to create a highly linear polymer chain with minimal branching?

2. The carbon atoms at the ends of a straight-chain alkane are termed as:

3. What is the major organic product (X) formed in the following two-step synthesis?

4. A compound is classified as non-aromatic if:

5. Polymerization is generally defined as a chemical process where:

6. A cyclic, planar, fully conjugated system that contains electrons (e.g., electrons) is classified as:

7. What is the minimum number of carbon atoms required for a compound to be classified as an alkyne?

8. The product of a Friedel–Crafts Acylation is generally less reactive toward a second electrophilic substitution than the starting benzene ring. This is due to the acyl group () being a:

9. Which of the following is an advantage of Friedel–Crafts Acylation over Alkylation?

10. Which type of addition is characteristic of the reaction of with an alkene in an inert solvent?

11. What are the products of the ozonolysis of 2-Methylbut-2-ene ()?

12. The preference of alkanes to undergo substitution reactions rather than addition reactions is due to:

13. Which of the following PAHs is considered one of the most potent carcinogens and is found in high concentrations in cigarette smoke and coal tar?

14. Polyvinyl Chloride (PVC) is considered a thermoplastic material, meaning it:

15. The free rotation about the single bond in alkanes leads to the existence of different spatial arrangements known as:

16. A compound with the molecular formula can represent either a simple alkyne or:

17. Which of the following conditions is most suitable for the dehydrohalogenation of an alkyl halide ()?

18. The nitration of benzene is an example of which general class of organic reaction?

19. What is the correct IUPAC name for the aromatic compound with two nitro groups attached to the benzene ring at positions 1 and 4?

20. The primary reason the Methyl group () is an activating and -directing group is its ability to donate electrons via:

21. But-1-yne and Buta-1,3-diene are examples of which type of isomerism?

22. Friedel–Crafts Acylation requires more than one full equivalent of the catalyst (often to equivalents). This is because:

23. What is the sum of the stoichiometric coefficients of and in the balanced equation for the complete combustion of Propane ()?

24. The second elimination step, converting a haloalkene into an alkyne, is often difficult because it removes a hydrogen from a carbon that is part of a double bond. What extremely strong base is required to complete this step, especially for terminal alkynes?

25. When naming a substituted benzene derivative, the two substituents are at the 1 and 3 positions. Which common prefix is used to denote this arrangement?

26. Fluorination of benzene is typically avoided in a laboratory setting because the reaction is:

27. When But-2-ene () undergoes ozonolysis, the single organic product obtained after reductive workup is:

28. When a substituent donates electrons to the ring via resonance, the electron density is primarily increased at which positions?

29. The bromination of benzene is generally preferred over the chlorination in many laboratory syntheses because:

30. In the reaction , the bond of the benzene ring is broken, and a new bond is formed. This step is a characteristic of:

1. The reaction of an internal alkyne with in an inert solvent results in the formation of a product with which stereochemistry?

2. The addition of to Propene () follows which of the following rules for predicting the major product?

3. Identify the total number of primary carbon atoms in the structure of 2,2-Dimethylpropane (Neopentane).

4. Which of the following classes of hydrocarbons is generally called Paraffins?

5. The resonance energy of Benzene, which quantifies its extra stability due to delocalization, is approximately:

6. How many total structural isomers (including chain and position) are possible for the molecular formula ? (Exclude geometrical isomers).

7. Hydrocarbons containing carbon-carbon double bonds are classified as:

8. The free rotation about the single bond in alkanes leads to the existence of different spatial arrangements known as:

9. Which compound exhibits Chain Isomerism with -Butane ()?

10. In the preparation of ethene () via Kolbe's electrolytic method, the starting material is the aqueous solution of the sodium or potassium salt of which carboxylic acid?

11. The hybridization of the carbon atoms involved in the triple bond of an alkyne is:

12. Polyethylene (PE) is formed from the monomer Ethene. What is the repeating structural unit in the Polyethylene chain?

13. According to Hückel's Rule, which of the following -electron counts is characteristic of an anti-aromatic compound?

14. When Methane is heated with oxygen at high pressure () in the presence of Copper () catalyst, the primary product is:

15. Which of the following numbers of electrons is consistent with Hückel's rule for an aromatic compound?

16. The electrophile that attacks the benzene ring during the nitration reaction is:

17. The Kekulé structure of benzene proposed that the molecule has:

18. The dehydrohalogenation of a terminal geminal dihalide (1,1-dihalide) primarily yields which type of alkyne?"

19. If 1-Propanol () is dehydrated with concentrated at , what is the product?

20. What is the major product (M) of the reaction when Benzene is treated with in the presence of anhydrous , followed by and ?

21. The -electron count in the smallest aromatic PAH, Naphthalene, is:

22. The first molecule of is added to an alkyne following which rule?

23. When 1-Butene reacts with in the absence of peroxides, the major product is 2-Bromobutane. This is an example of an addition reaction that follows:

24. Which product is formed when is added to a terminal alkyne like Prop-1-yne in the presence of and ?

25. Which of the following reagents will react with But-1-yne but not with But-2-yne?

26. The addition of to 2-Methylpropene () follows Markownikov's rule. What is the structure of the carbocation intermediate?

27. The reaction of an alkene with hydrogen gas () in the presence of a metal catalyst (, , or ) is known as:

28. The hydrogenation of -Xylene () using and under mild conditions results in what major product (L)?

29. Which statement accurately describes the relationship between -Hexane and 2-Methylpentane?

30. If the temperature is too high during the nitration of benzene, the formation of which product is favored?

31. Which of the following is the condition for a pair of compounds to be metameric isomers?

32. The product of a Friedel–Crafts Acylation is generally less reactive toward a second electrophilic substitution than the starting benzene ring. This is due to the acyl group () being a:

33. Which set of reagents is used to convert an alkene to a corresponding alkane?

34. Ozonolysis of 2-Butene () followed by treatment with yields which product?

35. What are the products of the complete combustion of any alkane in the presence of excess oxygen?

36. What distinguishes a cis-isomer from a trans-isomer in a disubstituted alkene?

37. The stability of the Benzene ring is due to the fact that all six carbon atoms are:

38. What is the common name of the alkane with four carbon atoms that exhibits chain isomerism with -Butane?

39. An alkene yields one mole of and one mole of (Methyl Ethyl Ketone) upon ozonolysis. What was the starting alkene?

40. A significant limitation shared by both Friedel–Crafts alkylation and acylation is that the reaction:

41. What is the correct IUPAC name for the aromatic compound with two nitro groups attached to the benzene ring at positions 1 and 4?

42. The correct representation of the -electron system in Benzene according to the Modern Theory is:

43. When Propyne is treated with dilute in the presence of (Kucherov's reaction), the final stable product obtained is:

44. Polyvinyl Chloride (PVC) is considered a thermoplastic material, meaning it:

45. Which of the following is not a structural isomer of -Pentane ()?

46. How many total bonds and bonds are present in a molecule of But-2-yne ()?

47. The intermediate formed by the reaction of the electrophile () and the benzene ring is known as the complex. This intermediate is stabilized by:

48. Which of the following conditions is not a requirement for a compound to be considered aromatic?

49. Ethene () is the simplest alkene. Which of the following is true about its structure?

50. Friedel–Crafts Acylation requires more than one full equivalent of the catalyst (often to equivalents). This is because: