Answer:
Density of the He atom = 12.69 g/cm³
Explanation:
From the information given:
Since 1 mole of an atom = 6.022x 10²³ atoms)
1 atom of He =
The volume can be determined as folows:
since the diameter of the He atom is approximately 0.10 nm
the radius of the He = = 0.05 nm
Converting it into cm, we have:
Assuming that it is a sphere, the volume of a sphere is
=
=
=
Finally, the density can be calcuated by using the formula :
D = 12.69 g/cm³
Density of the He atom = 12.69 g/cm³
Boiling point of a compound is determined by the strength of intermolecular forces of attraction between the molecules present in it. Stronger the intermolecular forces of attraction, higher will be the boiling point.
Ionic compounds show ion-ion interactions which are the strongest among all. Ion-dipole interactions are shown when ionic solutes are dissolved in polar solvents. Hydrogen bonding is also a relatively stronger force that is present between H atom and an electronegative atom like F, O and N() . All polar molecules show dipole-dipole interaction (
and
). Dispersion forces are the weakest intermolecular forces due to momentary dipoles between electron clouds and nucleus.
Among the given compounds, has dispersion forces as the major intermolecular forces of attraction. So they they exhibit the weakest IMF, hence have the lowest boiling point.