忿6-20.
A 4.476-g sample of apetroleum product was burned
inatube furnace, and the SO2 produced was col-
lected in 3% H,O>. Reaction:
SO2(9) 十 H202 一 H2S0O4
A 25.00-mL portion of 0.00923 M NaOH was intro-
duced into the solution of H2SO4, following which
the excess base was back-titrated with 13.33 mL of
0.01007 M HClL Calculate the parts per million of
sulfur in the sample.
