Why do metals tend to lose electrons and nonmetals tend to gain electrons when forming ions?
Nonmetals tend to gain electrons in order to achieve a full outer shell, so they are said to have high electronegativities.
Alkaline metals, for example, would find it much easier to lose electrons than gain electrons, so they are not very electronegative. On the other hand, halogens such as chlorine only need to gain one electron to form a full outer shell. This is much easier than losing seven electrons instead.
When it comes to transition metals it is a little more complicated, but like many other metals, they also have low electronegativities.
Transition metals have