Question

During the perparation of `H_(2)S_(2)O_(s)` (per disulphuric acid) `O_(2)` gas is also released at anode as byproduct. When `9.72 L` of `H_(2)` releaseds at cathode and `2.35 L O_(2)` at anode the weight `H_(2)S_(2)O_(8)` depostited at the cathode is .
A. ` 87. 12`
B. ` 48. 65`
C. ` 83. 42`
D. ` 51. 74`

Answer 1

Correct Answer - B
` 2HSO_4^(-) rarr H_2S_2O_8 +2e`
` 20^(2-) rarr O_2 +4e`
`(2.35)/(22.5) =0. 105 0.42 mole`
`H^+ + 2e rarr H_2`
Mole of e for ` H_2 S_2O_8 =0. 87 - 0. 42 =0. 45 ` mole
` :.` Mole of ` H_2 S_2 OO_8 =0. 225 "mole" = 43. 65 g`.