1.H:Cl:O=1:1:4
2.H:Cl:O=1:35.5:64
3.Masa moleculara HClO4=1*1+1*35.5+4*16=1+35.5+64=100.5g
4.100.5gHClO4............1gH.............35.5gCl............64gO
100g............................x.................y......................z
x=1*100/100.5=0.99%H
y=35.5*100/100.5=35.32%Cl
z=64*100/100.5=63.68%O
5.1mol HClO4...................64gO
3moli HClO4.....................x
x=64*3/1=192gO
6.100.5g HClO4..................64gO
x.......................................32gO
x=100.5*32/64=50.52g HClO4