Question

Why the colour of oxallix acid chnges in titration?

Answer 1

A pH indicator is a substance that it changes its colour in response to a chemical change. An acid-base indicator changes its colour depending on the pH (e.g., phenolphthalein). ... A drop of indicator solution is added to the titration at the start; at the endpoint has been reached the colour changes.

Answer 2

A drop of indicator solution is added to the titration at the start: at the end point has been reached the colour change...!