# Which species undergoes a loss of electrons in this equation: Mg(s) + 2Ag^+(aq) -> Mg^(2+)(aq) + 2Ag(s)?

$M g \left(s\right)$
In this reaction, $M g \left(s\right)$ with a net charge of $0$ (oxidation state of $0$) reacts with a solution containing $A {g}^{+}$ ions. The products are $M {g}^{2 +} \left(a q\right)$ and solid $A g$. We can see that $M g \left(s\right)$ has been oxidized, since it's oxidation state raised from $0$ to $+ 2$. Therefore, $M g \left(s\right)$ has lost electrons to become a cationic species.