Answer: become more negative
Step-by-step explanation:
Neutrons have a neutral charge, sometimes denoted
; protons have a positive charge, sometimes denoted
; and electrons have a negative charge, sometimes denoted
. Adding negative molecules is like adding negative numbers; say you start with Tn²⁺ and you add 3 electrons. That 2+ becomes a 1-, or just a -; Tn⁻, because +2 - 3 = -1.
I hope this helps! :)