A sulfonic acid is an oxoacid that has the following general structural formula.
In the most common sulfonic acids, R is either an alkyl group (alkanesulfonic acid) or an aryl
group (arenesulfonic acid).
Using the symbol Ms, methanesulfonic acid can be shown conveniently as MsOH.
Using the symbol Ts, p-toluenesulfonic acid can be shown conveniently as TsOH.