Answer: Ionic Compound
Step-by-step explanation:
An ionic compound is formed when an element completely transfers its valence electron to another element. The element which donates the electron is known as electropositive element or the metal and the element which accepts the electrons is known as electronegative element or non metal.
A covalent compound is formed when an element shares its valence electron with another element. This bond is formed between two non metals.
Mercury flouride contain ionic bonds as it is made up of mercury metal and fllourine non metal.