it will lose 3 electrons
3
Iodine tends to gain one electron when it forms an ion.
An ionic bond.
Sodium loses one electron to form a Na+ ion. Sulfur gains two electrons to form a sulfide ion, S2-.
when it forms an ion it would gain two electrons, becoming negatively charged (2-)
Se will gain electrons
A neutral Chromium atom loses 3 electrons to become a Chromium (III) ion.
Nitrogen is a unique element. It can loose one, two, three, four, or even five electrons. It can also gain one, two, or three electrons. These are not the only possibilities, however they are the most common.
It needs to gain 3 electrons than to lose 5 electrons. So phosphorus has to gain 3 electrons.
Lead is a metal that forms a positively charged cation. It must lose electrons.
metals
nonmetals