KMnO4
mKMnO4=39+55+4*16 = 158 g/mo
1 mol = 158 g/mol
x mol = 8g
x=8/158=0,05
1 mol = 6.02*10²³cz.
0.05 mola = x
x=0.05*6.02*10²³ = 0,301*10²³
Na2CO3
mNa2CO3=23*2+12+16*3=106
1 mol = 106 g/mol
x mol = 5 g
x=5/106=0,047
1mol = 6.02*10²³cz
0.047 = x
x=0.047*6.02*10²³≈0,29*10²³
K3PO4
m=3*39+31+4*16 =212
1 mol =212
x mol = 9
x=9/212=0,042
1 mol= 6.02*10²³
0.042 mola = x
x=0.042*6.02*10²³ ≈0,25*10²³