`25 mL ` of `H_(2)O_(2)` solution were added to excess of acidified solution of `KI`. The iodine so liberated required `20 mL` of `0.1N Na_(2)S_(2)O_(3)` for titration Calculate the strength of `H_(2)O_(2)` in terms of normalility, percentage and volumes.
(b) To a `25 mL H_(2)O_(2)` solution, excess of acidified solution of `KI` was added. The iodine liberated required `20 mL` of `0.3N` sodium thiosulphate solution. Calculate the volume strength of `H_(2)O_(2)` solution.

Options

A. `3.6g`
B. `0.8g`
C. `4.2g`
D. `0.98g`

Answer

D

Explanation

`(w)/(49) = (20 xx 5.6)/(5.6 xx 1000)`, wt of `K_(2)Cr_(2)O_(7) = 0.98g`