Answer:
Li⁻
Explanation:
# of protons = # element on the Periodic Table.
# of protons (+) + # of electrons (-) = overall charge
3 protons is the 3rd element on the Periodic Table: Lithium
All elements on the Periodic Table have a neutral charge. Lithium neutral has 3 protons and 3 electrons.
We are given 4 electrons; 3 + -4 = -1 charge overall.
Therefore, our ion is Li⁻
