 from {HEAD ~ about 10 mole percent} to {TAIL ~ about 25 mole percent} of the ampholytic ion pair 
to
from { HEAD ~ about 10 mole percent } to { TAIL ~ about 25 mole percent } of the ampholytic ion pair
OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH