An amount of CaHO solution was poured into a baker and a piece of litmus paper was added. Dilute phorsphic acid was added a little at a time with stirring until the litmus paper just turned purple. The resulting solution was exposed to dryness. (a)What was the colour of the litmus paper in the CaHO (b)What was the colour change of the litmus paper indicate. (c) What substance was left after the evaporation. (d) Write a balanced chemical equation reaction that took place.​