Liquid butane c4h10 and liquid propane c3h8 are stored in cylinders, to be used as fuels. the normal boiling point if butane is -0.5 celcius and heat of vaporization is 23.1kj/mol. the corresponding values for propane are -42.5 celcius and 15.4 kj/mol.

1.) how much energy is required to vaporize 185g of butane at its boiling point? the heat of vaporization of butane is 23.1kj/mol.

2.) what volume will 185g of butane occupy at 745 torr and 35 celcius?

you need to take a look at the periodic system in order to sort these elements into pairs that would most likely exhibit similar chemical properties. first, you need to find elements that are found in the same group (groups are vertical in the periodic system), and then to see whether they have the same valence number. if they meet these criteria, they will have similar properties.

the first pair: ne (neon) and kr (krypton), are noble gases found in group 8

the second pair: li (lithium) and k (potassium), found in group 1

the third pair: s (sulfur) and te (tellurium), found in group 6

the correct answer would be b) volume versus temperature, because they are also directly proportional.