<span>первая
1) CaC2 + 2H2O = Ca(OH)2 + C2H2
2) C2H2 + H2O = CH3CHO
CH3CHO + H2 = CH3CH2OH
3)CH3CH2OH + CuO = CH3CHO + Cu + H2O
СH3CHO + Ag2O = CH3COOH + 2Ag
вторая
1) С + 2H2 = CH4
2)CH4 + CL2 = CH3CL + HCL
3) 2CH3CL + 2Na = C2H6 + 2NaCL
C2H6 = C2H4 + H2
третья
1) С2H4 + HBr = C2H5Br
2) C2H5Br + NaOH = C2H5OH + NaBr
3) C2H5OH + CH3COOH = CH3COOC2H5
четвертая
1) CH3COOH + H2 = CH3CHO + H2O
2) СH3CHO + Ag2O = CH3COOH + 2Ag
3) CH3COOH + NaOH = CH3COONa + H2O
пятая
1) C2H2 + H2O = CH3CHO
2) CH3CHO + Ag2O = CH3COOH + 2Ag
3) CH3COOH + C3H7OH = CH3COOC3H7 + H2O
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вроде так
Ca3(PO4)2+3Na2CO3=3CaCO3+2Na3PO4
2Al+6HCl=2AlCl3+3H2
n(H2)=10/22.4=0.45 моль
по уравнению реакции на 2 моль алюминия приходится 3 моль водорода, значит n(Al)=0.45*2/3=0.3 моль
m(Al)=27*0.3=8.1 г