Because they are either losing or gaining an electron
A negative change.
it has no chrage 0 (electrical)
Alkali metals forn cations with the chrage +1.
i do not know but i think its 15
This is the electrical charge of the ion.
An ion has an electrical charge.
An ion is an atom (or group of atoms) with an electrical charge.
The name given to the electrical charge on an ion is a oxidation number. The charge of the ion typically formed by strontium is 2 plus.
Yes
Gained or lost electron(s).
no
a formal 1 negative