The quantity of atmospheric SO2(g) can be determined by reaction with aq), accor
ID: 834290 • Letter: T
Question
The quantity of atmospheric SO2(g) can be determined by reaction with aq), according to the balanced chemical equation shown below. The amount of sulfuric acid produced can be determined by titration with sodium hydroxide of known concentration. An 593.0 gram sample of an air that is known to contain sulfur dioxide was reacted with excess hydrogen peroxide. Given that 18.50 mL of a 0.00250 M NaOH(aq) were required to neutralize the H2S04(aq) produced, calculate the mass percentage of SO2(g) in the air sample.Explanation / Answer
H2O2 + SO2 => H2SO4
H2SO4 + 2 NaOH => Na2SO4 + 2 H2O
Moles of NaOH = volume x concentration of NaoH
= 18.50/1000 x 0.00250 = 4.625 x 10^(-5) mol
Moles of SO2 = moles of H2SO4 = 1/2 x moles of NaOH
= 1/2 x 4.625 x 10^(-5) = 2.3125 x 10^(-5) mol
Mass of SO2 = moles x molar mass of SO2
= 2.3125 x 10^(-5) x 64.064 = 0.00148148 g
Mass percent of SO2 = mass of SO2/mass of sample of air x 100%
= 0.00148148/593.0 x 100%
= 2.498 x 10^(-4)% = 2.50 x 10^(-4)%