Final answer:
Ethanol, having the lowest molecular weight and fewer hydrogen bonds compared to the other alcohols in the question, will have the lowest boiling point and thus will boil first.
Step-by-step explanation:
The question is asking which of the given molecules will boil first when mixed together and heated: 2-butanol, 1-hexanol, or ethanol. The boiling point of a compound is influenced by the molecular weight and the type of intermolecular forces present, such as hydrogen bonding. Among the given options, ethanol (CH₃CH₂OH) has the lowest molecular weight and fewer hydrogen bonds compared to the other alcohols mentioned, which suggests it will have the lowest boiling point and therefore, it will boil first. The order of increased boiling points in a generic manner would be due to a combination of molecular mass and the strength of hydrogen bonding present in the molecules. Although not mentioned in the given options, alkanes with one to four carbon atoms are gases at room temperature, which indicates relatively lower boiling points compared to alcohols of comparable molar mass like methanol.