1.

NaOH + HCl --> NaCl+H2O (1)

2NaOH +H2SO4 --> Na2SO4 +2H2O (2)

giả sử nNaOH (1)=x(mol)

nNaOH(2)=y(mol)

=>x+y=0,3.2=0,6(I)

theo (1) : nNaCl=nNaOH(1)=x(mol)

theo (2) : nNa2SO4=1/2nNaOH(2)=0,5y(mol)

=>58,5x+71y=40,1(II)

từ (I,II)

=>{x=0,2(mol)y=0,4(mol){x=0,2(mol)y=0,4(mol)

theo (1) : nHCl=nNaOH(1)=0,2(mol)

=>x=CM dd HCl=1(M)

theo (2) : nH2SO4=1/2nNaOH(2)=0,2(mol)

=>y=1(M)