S1U1L1F4O1N1A1T1I1N1G2
15 points
SULFONATING is validvalid
SULFONATE, [v SULFONATED, SULFONATES, SULFONATING] : SULFONATION [v]
SULFONATE, to convert into sulphonic acid, also SULPHONATE [v]
SULFONATE, [v SULFONATED, SULFONATES, SULFONATING] : SULFONATION [v]
SULFONATE, to convert into sulphonic acid, also SULPHONATE [v]