Question

Question #3b9e4

Answer 1

= 4,6%

Explanation:

since NaClO is reduced to NaCl and `Na_2S_2O_3` is oxidized to `Na_2S_4O_6`
the balanced reaction in ionic form is: `2H^+ + ClO^- +2S_2O_3^(2-) =Cl^- +S_4O_6^(2-) + H_2O`
The mmol of sodium thiosulfate are 0.715 mL x 0.15 M = 0,107 While the mmol of NaClO (74,44 g/mol) are the half (0,0535). That are 0,0535x 74,44g/mol= 3,9 mg of NaClO= 0,00399 g.
the percent by weight of NaOCl in the bleach sample is`(0,00399g)/(0.087 g) 100` = 4,6%