Question

Gasoline is primarily a mixture of hydrocarbons and is sold with an octane rating that is based on a comparison with the combustion properties of isooctane. Gasoline usually contains an isomer of isooctane called tetramethylbutane (C8H18), which has an enthalpy of vaporization of 43.3 kJ/mol and a boiling point of 106.5°C. Determine the vapor pressure of tetramethylbutane on a very hot summer day when the temperature is 38°C.

A. 47.9 torr
B. 67.8 torr
C. 89.3 torr
D. 80.3 torr
E. 36.7 torr

Air (consisting mostly of nitrogen (N2), oxygen (O2), and argon (Ar)) dissolves in water due to?

A. dipole-induced dipole forces.
B. ion–dipole forces.
C. dipole–dipole forces.
D. hydrogen bonding.
E. dispersion forces.

Thanks!