A Level Chemistry OCR Practice Exam

Which type of bond can be found in unsaturated hydrocarbons?

1. Single bonds only

2. Multiple bonds

3. Ionic bonds only

4. Nonpolar covalent bonds only

The correct answer is: Multiple bonds

Unsaturated hydrocarbons are characterized by the presence of multiple bonds between carbon atoms, specifically double or triple bonds. These multiple bonds occur in alkenes, which have at least one carbon-carbon double bond, and alkynes, which contain at least one carbon-carbon triple bond. The presence of these bonds distinguishes unsaturated hydrocarbons from saturated hydrocarbons, which only feature single bonds. The presence of multiple bonds not only affects the chemical reactivity of the molecules but also influences their physical properties, such as melting and boiling points. Hence, in the context of unsaturated hydrocarbons, the correct identification of the type of bond present is essential for understanding their structure and reactivity in organic chemistry.