{HEAD ~ Acids} such as sulfuric, hydrochloric, hydrobromic, phosphoric, {TAIL ~ trifluoroacetic} and trifluorosulfonic are acceptable 
such as
{ HEAD ~ Acids } such as sulfuric , hydrochloric , hydrobromic , phosphoric , { TAIL ~ trifluoroacetic } and trifluorosulfonic are acceptable
HEAD HEAD HEAD HEAD HEAD REL REL OTH OTH OTH OTH OTH OTH OTH OTH TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH