MCQs on Alkene

Alkenes are unsaturated hydrocarbons. There is at least one C-C double bond present in alkenes. The general formula of an alkene is C_nH_2n. They are also known as olefins due to oil forming nature. Due to weak pi bond and loosely held electrons, alkenes are readily attacked by electrophilic reagents.

1. Which of the following compounds react most readily with Br_(g)?

(a) C₂H₂

(b) C₃H₆

(c) C₂H₄

(d) C₄H₁₀

2. When propene reacts with HBr in the presence of peroxide, it gives rise to

(a) allyl bromide

(b) isopropyl bromide

(c) n-propyl bromide

(d) 3-bromopropane

3. Find the alkene with maximum stability

(a) cis-2-Butene

(b) trans-2-Butene

(c) 1-Butene

(d) All have the same stability

4. Ethylene bromide on treatment with Zn gives

(a) Alkyne

(b) Alkene

(c) Alkane

(d) All of the above

5. Which of the following reactions is common in alkenes?

(a) Addition

(b) Elimination

(c) Substitution

(d) Superposition

6. Cis-trans isomerism in alkenes is due to

(a) chiral carbon

(b) free rotation about single bond

(c) free rotation about the double bond

(d) restricted rotation about the double bond

7. Baeyer’s reagent is used to detect

(a) glucose

(b) double bonds

(c) oxidation

(d) reduction

8. Which of the following will form 2 acetaldehyde molecules on ozonolysis?

(a) 1-pentene

(b) 2-pentene

(c) 1-butene

(d) 2-butene

9. Which of the following reagents will form 1-propanol from propene?

(a) B₂H₆, H₂O₂, OH^–

(b) Aq. KOH

(c) H₂O, H₂SO₄

(d) Hg(OAc)₂, NaBH₄/H₂O

10. Geometrical isomerism is exhibited by

(a) 2-Butene

(b) 2-Butyne

(c) 2-Butenol

(d) Butanol

Answer

Further reading:

• NEET Chemistry Syllabus
• NEET Chemistry Important Topics
• NEET Chemistry MCQs
• How to Score 160 Plus in NEET Chemistry
• NEET Chemistry Weightage
• Chemistry Formulas for NEET