# The R group for serine is -CH_2-OH. In the ionized form, serine has what structural formula?

The general formula for an amino acid is usually written as $\text{H"_2"NCHRCOOH}$ or $\text{RCH(NH"_2")COOH}$.
"H"_3stackrelcolor(blue)("+")("N")"CHRCO"stackrelcolor(blue)("-")("O")