Volumetric Analysis Help!!!

hey

Many transition ometals occur naturally as sulfides. The follwing procedure was used to determine the sulfur conten of a particular metallic sulfide.
0.800g or metallic sulfur was heated un a stream of oxygen until reaction was complete and the sulfur dioxide produced, after colling, was absorbed in excess aqueous hydgroen peroxide ti firn sykfyruc acud, 25.0mL of 0.2000molL^-1 sodium hydroxidde solution was required for complete netraulisation of sulfuric acid,

Calculate, 

The number of moles of sulfuric acid formed from the sulfur dioxide,

The mass (in g) in this sulfuric acid,

The percentage (by mass) of sulfur in the metallic sulfide.

 

understand part b, c just need help figuring how to start the equation for a. cannot start b c as this is a multistep process 

 

figuring out both molar masses of H2SO4 and SO2

know that this is a 1;1 ratio,

figured out the equation 

SO2 + H2SO2 ---> H2SO4

 

The equation you figured is correct.

The number of moles of sulfuric acid formed from the sulfur dioxide?

For the complete neutralization of sulfuric acid 25.0 mL of 0.2000 mol. L-1 of sodium hydroxide.so, the balanced neutralization reaction will be this

H2SO4 + 2 NaOH → Na2SO4 + 2 H2O

in the reaction above 2 mol of NaOH reacting with 1 mol of H2SO4. So, lets find out how many moles of NaOH is required here in the given problem to completey neutralize the H2SO4.

Molarity = moles / volume

.2 = moles / .025 = .005 moles of NaOH so,

.005NaOH x 1 mol H2SO4/ 2 mol NaOH = .0025 mol H2SO4

The mass (in g) in this sulfuric acid ? just multiply the moles of H2SO4 with the molar mass

The percentage (by mass) of sulfur in the metallic sulfide?use the formula of percentage by mass formula

mass of H2SO4(found above)/ .8 g ( mass of metal sulfide) x 100% = ?