What is the density of aluminum chloride vapor (AlCl3) at 498 K and 0.939 atm? 1.24 g/L
3.06 g/L
5.17 g/L
7.42 g/L

B  3.06 g/L

Explanation:

formula for density is d = PM / RT

1. find given: P(pressure) = 0.939 atm, M(molar mass) = 133.33, R = 0.0821, T(temperature) = 498 K

2. plug in:  d = 0.939*133.33 / 0.0821*498 = 3.0621113 which rounds to 3.06 g/L

vanderwaal's forces of attraction are the electrostatic intermolecular forces that exist in a molecule due to the temporary or permanent dipoles that are developed in a molecule. in , the major intermolecular forces are dipole-dipole interactions as the molecule is polar (bent structure). so the vanderwaal's forces of interaction in between molecules are the permanent dipole-dipole interactions that develop due to the dipole that exists in between the polar h - s bond. the positively charged hydrogen atom is attracted towards the negative end of the dipole that is sulfur of the adjacent molecule. therefore, these forces of attraction are relatively stronger than that of london dispersion forces that exist in non polar molecules.

i think it's c. if you look search electronic symbol on google and then click on wiki it shows you a