Why Is Phenolphthalein A Good Indicator?

A strong acid- strong base titration is performed using a phenolphthalein indicator.

Phenolphtalein is chosen because it changes color in a pH range between 8.3 – 10.

It will appear pink in basic solutions and clear in acidic solutions.

Titration: Titration of an acid-base system using phenolphthalein as an indicator.

Why is phenolphthalein used as an indicator?

Phenolphthalein is often used as an indicator in acid–base titrations. For this application, it turns colorless in acidic solutions and red in basic solutions. When a base is added to the phenolphthalein, the equilibrium shifts, leading to more ionization as H+ ions are removed.

Why is phenolphthalein a good indicator for weak acid strong base titration?

Answer and Explanation: During a titration of a weak acid and a strong base, the equivalence point is likely to be reached when the resultant solution is basic (i.e., pH greater than 7). The pH range of phenolphthalein is known to be between 8.3 and 10.0.

Why would phenolphthalein not be a suitable indicator?

Why is phenolphthalein not a suitable indicator for titrating weak base against strong acid? Because (as the names suggest) the equivalence point of a titration will result in an acid salt. The greater acidity of the acid overcomes the basicity of the base. Thus it will occur at a pH less than 7.

How do you use phenolphthalein indicator?



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Using Phenolphthalein As An Acid – Base Indicator – YouTube


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