Answer:
MgO has a highest melting point
C5Br has lowesst
Explanation:
It takes a lot of energy to overcome the strong electrostatic forces of attraction between oppositely charged ions, so ionic compounds have high melting and boiling points. ... Magnesium oxide is made from ions with two charges (Mg 2+ and O 2-) and so has a much higher melting point of 2852°C.
