K2SO4
K:S:O=2:1:4
MK2SO4=2*39+32+4*16=174
174g K2SO4.................................78gK.........................32gS.................64gO
100gK2SO4......................................x................................y.......................z
x=44,82% K y=18,39% S z=36,78% O
3moli K2SO4= 3*174=522g K2SO4
1molK2SO4................................32g S
3moli..............................................a g S
A=96g S
