Which of the following indicators would be the best to use when 0.050 M benzoic acid (Ka = 6.6 × 10-5) is titrated with 0.05 M NaOH? Answer bromphenol blue, pH range: 3.0-4.5 bromcresol green, pH range: 3.8-5.4 alizarin, pH range: 5.7-7.2 phenol red, pH range: 6.9-8.2 phenolphthalein, pH range: 8.0-10.1