The graph shows the effect of pH on quenching of luminescence of tris(2,2 bipyridine)Ru(II) by 2,6-dimethylphenol. The ordinate, K_SV, is the collection of constants, k_q/(k_e + k_d), in the Stern-Volmer equation 18-25. The greater K_SV, the greater the quenching. Suggest an explanation for the shape of the graph and estimate pK_a for 2,6-dimethylphenol.

Equation 18-25

Transcribed Image Text:

OH Ru2+ 2,6-Dimethylphenol Tris(2,2'-bipyridineruthenium(II) 1 500 1 000 500 0 10 12 13 pH