On igniion, Rochelle salt `NaKC_(4) H_(4) O_(6). 4H_(2)O` (mol. Wt 282) is converted into `NaKCO_(3) (mol wt. 122).0.9546g` sample of the rochelle salt on ignition gives `NaKCO_(3)` which is titrated wih `41.72mL.H_(2)SO_(4)`. From the follwing data, find the percentage purtiy of the rochelle salt. The solution after neutralisation requires its `1.91 mL` of `0.1297N NaOH`. The `H_(2)SO_(4)` used for the neutralisation requires its `10.27mL` aganist `10.35mL` of `0.1297N NaOH`
