a) Gọi CTTQ của h/c là HxSyOz (x,y,z \(\in N\)*)
Ta có: \(x:y:z=\dfrac{2,04}{1}:\dfrac{32,64}{32}:\dfrac{65,31}{16}\)
\(=2,04:1,02:4,08\)
\(=2:1:4\)
\(\Rightarrow CTHH:H_2SO_4\)
b) Tương tự: \(x:y:z=\dfrac{40}{64}:\dfrac{20}{32}:\dfrac{40}{16}\)
\(=0,625:0,625:2,5\)
\(=1:1:4\)
\(\Rightarrow CTHH:CuSO_4.\)