HF:
a) dispersion force
b) dipole-dipole force
c) hydrogen bond

HF: hydrogen bond

Explanation:

The hydrogen bond is a type of interaction that is established between a molecule that presents hydrogen with another that presents an atom with a high electronegativity, such as oxygen, fluorine or nitrogen (O, F, N), joining covalently due to their opposite charges.

The hydrogen atom has a positive charge and is known as a donor atom. The oxygen, fluorine or nitrogen atom is the bond acceptor atom.

So:

HF: hydrogen bond

> b takes place in the gas phase in an isothermal tubular reactor. the feed is one mole of a per one mole of c, an inert. the entering temperature and pressure are 427°c and 10 atm, respectively. the gas constant r = 0.08206 atm · l/mol · k.