What is the reagent used in Horrock's apparatus for determining chlorine demand of water -
Horrock's apparatus is designed to find the dose of bleaching powder required for disjnfection of water. The indicator used is starch iodine indicator solution.Addition of the indicator to the cups with stock solution and water gives blue colour if there is free residual chlorine. Parks textbook of preventive and social medicine.K Park. Edition 23.Pg no: 729
Ohotoluidine
Methylene blue
Stach iodide indicator
Sodium bicarbonate
Environment and health