Using equation 18-5 and the pkin value you found, determine the ratio [in-]/[hin] at the ph in the middle of the range you studied (i. e., ph = 6.0 for bromocresol purple, ph = 7.0 for bromothymol blue, and ph = 7.7 for phenol red). show how you accomplished this. draw a conclusion about the relative concentrations of in- and hin at ph values very close to the pkin of the indicator.