Alkaline Earth Metals are the elements located in the second period from the left of the periodic table. These elements lose two electrons to form the stable octet when forming an ionic bond, resulting in a net charge of +2. Because they’re trying to get rid of those electrons to get to the stable octet, it’s easy to remove them - this means that the ionization energy of these elements is relatively low. Finally, since they’re looking to get rid of electrons, they certainly aren’t trying to gain any, meaning that their electronegativity is relatively low.
I think the answer is reversible. Reversible reaction is a kind of reaction which can react in both direction at the same time. And when the both side reactions get the same speed, the reaction is at a equilibrium state.
