From the substances provided below, choose the substance which has the weakest intermolecular forces.
Substance Vapor pressure at 20°C, torr
pentane (C5H12) 414.5
methanol (CH3OH) 97.3
1-butanol (C4H9OH) 7.1
1-butanol (C4H9OH)
methanol (CH3OH)
pentane (C5H12)