The abnormally high boiling point of HF as compared to HCl is primarily due to intermolecular forces of attraction called A)network bonds
B)electrovalent forces
C)hydrogen bonds
D)van der Waals forces

C)hydrogen bonds

Explanation:

The abnormally high boiling point of HF compared to HCl is primarily due to the intermolecular forces called hydrogen bonds.

Hydrogen bonds are intermolecular forces of attraction between polar molecules in which a hydrogen atom is directly joined to a highly electronegative atom (oxygen, nitrogen or fluorine).

Hydrogen bonds are very strong force of attraction compared to dipole - dipole attraction that holds the HCl together.

number of molecules / avogadro's number * molecule molecular = mass

explanation:

we define a gram-molecular weight as the mass of one mole of any element or compound. a mole contains avogadro's number of units (molecules) –  

6.022

x

10

23

. so, dividing the number of molecules by avogadro's number gives us the number of moles. multiplying that by the molecular weight gives us the mass. from the periodic table we find the gram-molecular weight of u to be238 and of f to be19. so,  

u

f

6

will have a gram-molecular weight of 352g.