Name the molecule C3H8.

Study for the IGCSE Edexcel Chemistry Test. Access flashcards and multiple choice questions with hints and explanations. Get ready for your exam!

Multiple Choice

Name the molecule C3H8.

Explanation:
Understanding how names reflect carbon count helps here. The general formula for alkanes is CnH2n+2, so for n = 3 you get C3H8. The three-carbon alkane is named propane, using the prefix prop- for three carbons and the -ane ending for a saturated hydrocarbon. A quick look at the structure CH3-CH2-CH3 confirms three carbon atoms arranged in a chain with the remaining hydrogens saturating the valences. There’s no branching for three carbons, so only one isomer exists. Compared to methane (one carbon) and ethane (two carbons) and butane (four carbons), C3H8 matches three carbons, so propane is the correct name.

Understanding how names reflect carbon count helps here. The general formula for alkanes is CnH2n+2, so for n = 3 you get C3H8. The three-carbon alkane is named propane, using the prefix prop- for three carbons and the -ane ending for a saturated hydrocarbon. A quick look at the structure CH3-CH2-CH3 confirms three carbon atoms arranged in a chain with the remaining hydrogens saturating the valences. There’s no branching for three carbons, so only one isomer exists. Compared to methane (one carbon) and ethane (two carbons) and butane (four carbons), C3H8 matches three carbons, so propane is the correct name.

Subscribe

Get the latest from Examzify

You can unsubscribe at any time. Read our privacy policy