Question

match the boiling points with the appropriate alkanes from the list below. 2 - methylpentane, hexane, 2,2 - dimethylbutane, heptane
boiling points compounds
50 °c select
60 °c select
69 °c select
98 °c select

Explanation:

Step1: Understand boiling - point trend

Boiling points of alkanes increase with increasing molecular weight and decrease with increasing branching. Heptane has 7 carbon atoms and the highest molecular weight among these, so it has the highest boiling - point. Hexane has 6 carbon atoms. 2 - methylpentane is a branched isomer of hexane and 2,2 - dimethylbutane is a more highly branched isomer of hexane.

Step2: Match boiling points

The most highly branched compound 2,2 - dimethylbutane has the lowest boiling - point among the C6 alkanes. So, 50 °C corresponds to 2,2 - dimethylbutane. 2 - methylpentane has a boiling - point higher than 2,2 - dimethylbutane but lower than hexane, so 60 °C corresponds to 2 - methylpentane. Hexane has a boiling - point of 69 °C. Heptane has the highest boiling - point of 98 °C among these compounds.

Answer:

50 °C: 2,2 - dimethylbutane
60 °C: 2 - methylpentane
69 °C: hexane
98 °C: heptane