In the reaction of sodium thiosulphate with `I_(2)` in aqueous medium, the equivalent mass of sodium sulphate

Options

A. Molar mass of sodium thisosulphate
B. The average of molar masses of `Na_(2)S_(2)O_(3)` and `I_(2)`
C. Half the molar mass of sodium thiosulphate
D. Molar mass of sodium thiosulphate `xx2`

Answer

A

Explanation

`2 Na_(2)S_(2)O_(3).5H_(2)O+I_(2) rarr 2NaI+Na_(2)S_(4)O_(6)`
or `2 S_(2)O_(3)^(2-) rarr S_(4)O_(6)^(2-)+2e^(-)`
Equivalent weight of `Na_(2)S_(2)O_(3).5H_(2)O`
`=("Mol. wt.")/1=248/1=248`.