3C2H4+2KMnO4+4H2O=3CH2OH-CH2OH+2MnO2+2KOH
3 2 2
n(C2H4)=0,672/22,4=0,03; n(KMnO4)=0,03*2/3=0,02; m(KMnO4)в р-ре =0,02*158=3,16;
m(KMnO4)р_ра =3,16/0,05=63,2; m(H2O)=63,2-3,16=60,04;
n(KOH)=0,02; m(KOH)=0,02*56=1,12;
W(KOH)= 1,12/(1,12+60,04)=0,0183(1,83%).
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