<span>CuO+H2SO4=CuSO4+H2</span>
<span><span>кол-во в-ва CuO=m/M=20/79=0,25 моль</span></span>
<span><span><span>кол-во в-ва H2SO4=21/98=0,21</span></span></span>
<span><span><span>m(CuSO4)=кол-во вещ-ва *M=0.21*159=33.4г</span></span></span>
CH3COH + Ag2O = CH3COOH + 2Ag
x/44 = 2.7/216
x = (44*2.7)/216 = 0.55 г
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