Cresol red has two transition ranges listed in Table 10-3. What color would you expect it to be at the following pH values?

(a) 0;

(b) 1;

(c) 6;

(d) 9

Table 10-3

Transcribed Image Text:

Acid color Transition Base Indicator range (pH) color Preparation Methyl violet Cresol red Violet 0.05 wt% in H,O 0.1 g in 26.2 mL 0.01 M NAOH. Then add ~225 mL H,O. 0.1 g in 21.5 mL 0.01 M NAOH. Then add -225 mL H,O. 0.1 g in 26.2 mL 0.01 M NaOH. Then add ~225 mL H,O. 0.1 wt% in H20 0.01 wt% in H2O 0.1 wt% in H0 0.1 wt% in H20 0.1 g in 14.3 mL 0.01 M NaOH. Then add ~225 mL H2O. 0.02 g in 60 mL ethanol. Then add 40 mL H,O. 0.1 g in 23.6 mL 0.01 M NaOH. Then add -225 mL H,O. 0.1 g in 18.5 mL 0.01 M NaOH. Then add ~225 mL H,O. 0.1 wt% in H20 0.1 wt% in H20 0.1 g in 16.0 mL 0.01 M NAOH. Then add ~225 mL H,O. 0.1 g in 28.2 mL 0.01 M NaOH. Then add ~225 mL H2O. 0.01 g in 50 mL ethanol. Then add 50 mL H,O. 0.0-1.6 Yellow 0.2-1.8 Red Yellow Thymol blue Cresol purple Erythrosine, disodium Methyl orange Congo red Ethyl orange Bromocresol green Methyl red Chlorophenol red Bromocresol purple p-Nitrophenol Litmus 1.2–2.8 Red Yellow 1.2-2.8 Red Yellow 2.2–3.6 Orange Red Red 3.1-4.4 Yellow 3.0-5.0 Violet Red 3.4-4.8 Red Yellow 3.8–5.4 Yellow Blue 4.8–6.0 Red Yellow 4.8–6.4 Yellow Red 5.2-6.8 Yellow Purple Yellow 5.6–7.6 Colorless 5.0-8.0 Red Blue Bromothymol blue Phenol red 6.0-7.6 Yellow Blue 6.4-8.0 Yellow Red Neutral red 6.8–8.0 Red Yellow Cresol red 7.2-8.8 Yellow Red See above. a-Naphtholphthalein Cresol purple Thymol blue Phenolphthalein Thymolphthalein Alizarin yellow 7.3–8.7 Pink Green 0.1 g in 50 mL ethanol. Then add 50 mL H2O. 7.6-9.2 Yellow Purple See above. 8.0-9.6 Yellow Blue See above. 8.0-9.6 Colorless Pink 0.05 g in 50 mL ethanol. Then add 50 mL H,O. 0.04 g in 50 mL ethanol. Then add 50 mL H,O. 0.01 wt% in H,0 0.1 g in 70 mL ethanol. Then add 30 mL H,O. 0.1 wt% in H0 8.3–10.5 Colorless Blue Yellow Orange-red Orange-brown Orange 10.1–12.0 Nitramine 10.8–13.0 Colorless Tropaeolin O 11.1–12.7 Yellow