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
I think that it is shear adhesion
In earths surface or the bottom of the Ocean
Group 7a would have an ion charge of -1 because it has 7 valence electrons and it wants to gain one more electron(which is negative) to have a full shell of 8
Here we apply the Clausius-Clapeyron equation:
ln(P₁/P₂) = ΔH/R x (1/T₂ - 1/T₁)
The normal vapor pressure is 4.24 kPa (P₁)
The boiling point at this pressure is 293 K (P₂)
The heat of vaporization is 39.9 kJ/mol (ΔH)
We need to find the vapor pressure (P₂) at the given temperature 355.3 K (T₂)
ln(4.24/P₂) = 39.9/0.008314 x (1/355.3 - 1/293)
P₂ = 101.2 kPa