Alkenes Knowledge-Based Download PDF

Questions

1. 1.

   What is the systematic IUPAC name of the alkene with the condensed structural formula $\text{CH}_3\text{CH}_2\text{C}(\text{CH}_3)=\text{CH}_2$?

   • A) 2-ethylprop-1-ene
   • B) 2-methylbut-1-ene
   • C) 3-methylbut-3-ene
   • D) 2-methylbut-2-ene
2. 2.

   Which statement correctly describes the hybridization of the carbon atoms and the composition of the double bond in ethene ($\text{C}_2\text{H}_4$)?

   • A) Both carbon atoms are $sp^3$ hybridized, and the double bond consists of two $\sigma$ bonds.
   • B) Both carbon atoms are $sp^2$ hybridized, and the double bond consists of one $\sigma$ bond and one $\pi$ bond.
   • C) Both carbon atoms are $sp$ hybridized, and the double bond consists of two $\pi$ bonds.
   • D) One carbon atom is $sp^2$ hybridized and the other is $sp^3$ hybridized, and the double bond consists of one $\sigma$ bond and one $\pi$ bond.
3. 3.

   Which observation confirms the presence of a carbon-carbon double bond when an unknown liquid hydrocarbon is treated with aqueous bromine at room temperature in the dark?

   • A) The reddish-brown colour of the solution rapidly fades to colourless.
   • B) A purple solution turns colourless while forming a dark brown precipitate.
   • C) A bright yellow crystalline precipitate forms upon gentle warming.
   • D) Vigorous effervescence occurs with the release of a colourless gas.
4. 4.

   Which of the following alkenes can exist as a pair of cis-trans (geometric) isomers?

   • A) But-2-ene
   • B) But-1-ene
   • C) 2-Methylpropene
   • D) Ethene
5. 5.

   What is the major organic product formed when propene reacts with hydrogen chloride ($\text{HCl}$) via electrophilic addition?

   • A) 2-chloropropane
   • B) 1-chloropropane
   • C) 1,2-dichloropropane
   • D) 2-chloropropene