Why is methanol (CH3OH) less soluble in hexane (C6H14) than pentanol (CH3CH2CH2CH2CH3OH)? Pentanol is a bigger molecule, therefore hexane can break its bonds more easily. Hexane can form hydrogen bonds with methanol and therefore repel it. Hexane is nonpolar and pentanol is more nonpolar due to its longer carbon-carbon chain. Pentanol can form hydrogen bonds but methanol can't. Hexane is polar and pentanol is more polar then methanol.