7. FeS2 --(1)-->SO2---(2)---> SO3---(3)---> H2SO4
\(n_{FeS_2}=\dfrac{1}{120}\left(mol\right)\)
Ở giai đoạn (1) , H=80 %=> \(n_{SO_2}=\dfrac{1}{120}.2.80\%=\dfrac{1}{75}\left(mol\right)\)
Ở giai đoạn (2) , H=60 %=> \(n_{SO_3}=\dfrac{1}{75}.60\%=\dfrac{1}{125}\left(mol\right)\)
Ở giai đoạn (3) , H=85 %=>\(n_{H_2SO_4}=\dfrac{1}{125}.85\%=6,8.10^{-3}\left(mol\right)\)
=> \(m_{H_2SO_4}=6,8.10^{-3}.98=0,6664\left(tấn\right)=666400\left(g\right)\)
=> \(m_{ddH_2SO_4}=\dfrac{666400}{98\%}=680000\left(g\right)\)



