The reaction of S(OH)₂ with trifluoroacetic acid is as follow,
Sr(OH)₂ + 2 F₃C-COOH → (F₃C-COO)₂Sr + 2 H₂O
Trifluoroacetic acid a derivative of Acetic acid. The pKa value (-0.3) of trifluoroacetic acid is much smaller than Acetic acid (i.e. 4.7). This increase in acidity is mainly due to three fluorine atoms (highly electronegative) attached at alpha carbon. Therefore, when trifluoroacetic acid is reacted with base like Strontium Hydroxide it donated its proton readily forming a salt like Strontium trifluoroacetate and water.