Given below are two statements : one is labeled as Assertion A and the other is labeled as Reason R.

Assertion A: Phenolphthalein is pH dependent indicator, remains colourless in acidic solution and gives pink colour in basic medium.

Reason R: Phenolphthalein is a weak acid. It doesn’t dissociate in basic medium.

In the light of the above statements, choose the most appropriate answer from the options given below.

<p>Phenolphtalein is a pH dependant indicator. It is a weak acid which is colourless in acidic medium but gives pink colour in basic medium. The pink colour is due to its conjugate form. Phenolphthalein dissociates in basic medium. Therefore, assertion is true but reason is false.</p><p><math><mrow><munder><mrow><mi>H</mi><mi>P</mi><mi>h</mi><mrow><mo> (</mo><mrow><mi>a</mi><mi>q</mi><mo>.</mo></mrow><mo>)</mo></mrow></mrow><mrow><mrow><mo> (</mo><mrow><mi>C</mi><mi>o</mi><mi>l</mi><mi>o</mi><mi>u</mi><mi>r</mi><mi>l</mi><mi>e</mi><mi>s</mi><mi>s</mi></mrow><mo>)</mo></mrow></mrow></munder><mo>? </mo><msup><mrow><mi>H</mi></mrow><mrow><mo>+</mo></mrow></msup><mo>+</mo><munder><mrow><mi>P</mi><msup><mrow><mi>h</mi></mrow><mrow><mo>−</mo></mrow></msup></mrow><mrow><mrow><mo> (</mo><mrow><mi>P</mi><mi>i</mi><mi>n</mi><mi>k</mi></mrow><mo>)</mo></mrow></mrow></munder></mrow></math></p>

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