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1. 下列化合物沸点最低是的（）。 A. 正辛烷 B. 3-甲基庚烷 C. 2,3-二甲基已烷 D. 正壬烷

Sep 24, 2024

D

Key Concept

Boiling points of alkanes

Explanation

The boiling point of alkanes generally increases with molecular weight and branching. Among the given options, n-nonane (正壬烷) has the highest molecular weight, while 2,3-dimethylhexane (2,3-二甲基已烷) has the lowest due to its branching, leading to a lower boiling point compared to the others. Thus, 正壬烷 (n-nonane) has the lowest boiling point.