a)2 KMnO4------->K2MnO4+MnO2+O2
n O2=3,36/22,4=0,15(mol)
Theo pthh
n KMnO4=2n O2=0,3(mol)
m KMnO4=0,3.158=47,4(g)
H%=40,4/47,4.100%=85,23%
b) n K2MnO4=n MnO2=n O2=0,15(mol)
m K2MnO4=0,15.197=29,55(g)
m MnO2=87.0,15=13,05(g)
m hh=29,55+13,05=42,6(g)
%m K2MnO4=29,55/42,6.100%=69,37%
%m MnO2=100-69,37=30,63%
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