question_answer

When soap is scrubbed on a stain of curry on a white cloth, why does it become reddish brown, and turns yellow again when the cloth is washed with plenty of water?

Answer:

The curry might contain turmeric powder which is the indicator of acids and bases. Soap being basic in nature turns the colour of the termeric from yellow to reddish brown. After washing with lot of water the soap is removed and the turmeric returns to its yellow colour.