Which is the most dense?

Question

CH4

NH3

NO

Ne

HF

Answer 1

i believe NH3 but I'm not sure

Answer 2

Gas phase densities:

CH4 - 0.717 kg/m^3 @ STP

NH3 - 0.694 kg/m^3 @ STP

NO - 1.270 kg/m^3 @ SP, 15 deg. C

Ne - 0.853 kg/m^3 @ SP, 15 deg. C

Liquid density:

HF - 1.24 g/cm^3 @ STP

Okay, so, because HF is a liquid at room temperature, unlike all the others in the list, it will be the most dense.

Answer 3

if i had to guess, id say NO, but im not sure