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What is If the second cup of Horrock's apparatus show blue color after 3 drops of starch-iodine indicator, what dose of bleaching power is required to disinfect 910 L? and explain in detail?
Dose = n x 2 gm for 455 litres n = no, of first cup which show distinct blue colour * n=2 (2nd cup - color change) n x 2 for 455 litres 4 gm for 455 litres 455 litres - 4 gm