Cresol Red?

[bullsfan1986]

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I was doing some passages from TBR gen chem and I noticed that in the first book, section V (buffers and titrations), passage 13 (p.335) there is a table with a bunch of different indicators. The indicator cresol red appears twice with 2 different pKa values corresponding to two very different pH ranges. I don't know whether this question has been asked before, but is this a typo or am I going crazy? Thanks.

 

[BerkReviewTeach]

I was doing some passages from TBR gen chem and I noticed that in the first book, section V (buffers and titrations), passage 13 (p.335) there is a table with a bunch of different indicators. The indicator cresol red appears twice with 2 different pKa values corresponding to two very different pH ranges. I don't know whether this question has been asked before, but is this a typo or am I going crazy? Thanks.

That's not a typo. It's a bizarre indicator that has two different color changes (caused by two different protons). It goes from red to yellow when deprotonated around 1.6 and then from yellow to blue when deprotonated around 8.0.