Question

Explain why in an attempt at electrolysis of water common salt solutions lose the color of added phenolphthalein, with the new addition of the indicator, it reports again, then loses again?

Answer 1

Phenolphthalein is an acid-base indicator that changes color depending on the hydrogen ion concentration in a solution. In an attempt at electrolysis of water with common salt solutions, the indicator loses its color at first due to the high concentration of hydrogen ions, but it reports again as the concentration decreases.

Step-by-step explanation:

Phenolphthalein is an acid-base indicator that changes color depending on the hydrogen ion concentration in a solution. In an attempt at electrolysis of water with common salt solutions, the hydrogen ions are either added or removed through chemical reactions. When the hydrogen ion concentration is high, phenolphthalein is colorless, but it turns red when the hydrogen ion concentration is low. Therefore, when the indicator is initially added, the color disappears because of the high concentration of hydrogen ions. However, as the concentration decreases during electrolysis, the color reappears.