Alkene MCQs

31. Which of the following is a correct structural formula for an alkene?

• A) CH₄
• B) C₂H₆
• C) C₄H₈
• D) C₆H₁₀
• Answer: C

32. What type of bonds are present in alkenes?

• A) One σ-bond and one π-bond
• B) Two σ-bonds
• C) One π-bond only
• D) Two π-bonds
• Answer: A

33. Alkenes can be synthesized from alkyl halides through:

• A) Halogenation
• B) Dehydrohalogenation
• C) Hydrolysis
• D) Hydration
• Answer: B

34. Which of the following reagents is used for the polymerization of alkenes?

• A) Platinum catalyst
• B) Heat and pressure
• C) Sulfuric acid
• D) Potassium permanganate
• Answer: B

35. Which of the following reactions can be used to produce an alkene?

• A) Hydrogenation of an alkyne
• B) Ozonolysis of an alkane
• C) Dehydrohalogenation of an alkyl halide
• D) Hydration of an alcohol
• Answer: C

36. Alkenes react with water in the presence of an acid to produce:

• A) Alcohols
• B) Aldehydes
• C) Ketones
• D) Carboxylic acids
• Answer: A

37. Alkenes undergo polymerization to form:

• A) Dienes
• B) Alkanes
• C) Polymers
• D) Ethers
• Answer: C

38. Which of the following products is formed when ethene reacts with chlorine?

• A) Ethylene glycol
• B) Dichloroethane
• C) Acetylene
• D) Propane
• Answer: B

39. The presence of a double bond in alkenes results in:

• A) Higher boiling point than alkanes
• B) Higher reactivity than alkanes
• C) Lower reactivity than alkynes
• D) Greater stability than alkanes
• Answer: B

40. Which of the following compounds is the starting material for the production of polyethene?

• A) Methane
• B) Ethene
• C) Propene
• D) Butene
• Answer: B