If you are asked to compare matter in solid, liquid, and gaseous states, which statement best defines a gas?

a).highest energy, highest molecular motion, and least dense packaging of molecules
b).highest energy, highest molecular motion, and most dense packaging of molecules
c).least energy, highest molecular motion, and least dense packaging of molecules
d).highest energy, least molecular motion, and least dense packaging of molecules

)benzene and toluene form nearly ideal solutions. consider an equimolar solution of benzene and toluene. at 20 °c the vapour pressures of pure benzene and toluene are 9.9 kpa and 2.9 kpa, respectively. the solution is boiled by reducing the external pressure below the vapour pressure. calculate (i) the pressure when boiling begins, (ii) the composition of each component in the vapour, and (iii) the vapour pressure when only a few drops of liquid remain. assume that the rate of vaporization is low enough for the temperature to remain constant at 20 °c.