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Part of the speciation graph of a commonly used red food dye is shown below. The molecular structures of both species whose concentrations are graphed are also given below as species 1 and species 2. Identify which species corresponds to which line and what is the value of pka. Red food dye speciation at different pH values % Species 100 90 80 70 60 50 40 30 20 10 0 0 1 2 PH 3 4 LO 5 ......... HO . ......... OH OH HO Red dye species 1 OH The value of pka for this substance is OH Red dye species 2 OH OH The dashed red line corresponds to OH OH OH The solid blue line corresponds to