a) Gọi \(\left\{{}\begin{matrix}n_{Mg}=a\left(mol\right)\\n_{Fe}=b\left(mol\right)\end{matrix}\right.\)

PTHH: Mg + H₂SO₄ --> MgSO₄ + H₂

             a--->a---------->a-------->a

            Fe + H₂SO₄ --> FeSO₄ + H₂

             b--->b----------->b------>b

=> \(m_{H_2SO_4}=98a+98b\left(g\right)\)

=> \(m_{ddH_2SO_4}=\dfrac{\left(98a+98b\right).100}{19,6}=500a+500b\left(g\right)\)

m_{dd sau pư} = 24a + 56b + 500a + 500b - 2a - 2b = 522a + 554b (g)

Có: \(C\%_{FeSO_4}=\dfrac{152b}{522a+554b}.100\%=7,17\%\)

=> a = 3b

\(C\%_{MgSO_4}=\dfrac{120a}{522a+554b}.100\%=16,98\%\)

b)

Có: \(\left\{{}\begin{matrix}a=3b\\24a+56b=1,92\end{matrix}\right.\)

=> a = 0,045; b = 0,015

\(n_{CuSO_4}=0,1.1=0,1\left(mol\right)\)

PTHH: Mg + CuSO₄ --> MgSO₄ + Cu

         0,045->0,045----->0,045

            Fe + CuSO₄ --> FeSO₄ + Cu

       0,015-->0,015----->0,015

=> \(\left\{{}\begin{matrix}n_{CuSO_4\left(dư\right)}=0,04\left(mol\right)\\n_{MgSO_4}=0,045\left(mol\right)\\n_{FeSO_4}=0,015\left(mol\right)\end{matrix}\right.\)

=> \(\left\{{}\begin{matrix}C_{M\left(CuSO_4\left(dư\right)\right)}=\dfrac{0,04}{0,1}=0,4M\\C_{M\left(MgSO_4\right)}=\dfrac{0,045}{0,1}=0,45M\\C_{M\left(FeSO_4\right)}=\dfrac{0,015}{0,1}=0,15M\end{matrix}\right.\)

\(n_{Ag_2O}=\dfrac{4.64}{232}=0.02\left(mol\right)\)

\(m_{dd_{HNO_3}}=300\cdot1.59=477\left(g\right)\)

\(Ag_2O+2HNO_3\rightarrow2AgNO_3+H_2O\)

\(0.02............................0.04\)

\(m_{AgNO_3}=0.04\cdot170=6.8\left(g\right)\)

\(m_{dd}=4.64+477=481.64\left(g\right)\)

\(C\%_{AgNO_3}=\dfrac{6.8}{481.64}\cdot100\%=1.4\%\)

Fe2O3+3H2SO4+->Fe2(SO4)3+3H2O

\(=>\dfrac{mH2SO4}{147}.100\%=20\%=>mH2SO4=29,4g\)

\(=>nFe2O3=\dfrac{1}{3}nH2SO4=\dfrac{1}{3}.\dfrac{29,4}{98}=0,1mol\)

\(=>a=mFe2O3=0,1.160=16g\)

\(=>C\%Fe2\left(SO4\right)3=\dfrac{0,3.400}{147+16}.100\%=73,7\%\)

cho cac axit :HCLO,HNO3,H2S,H2SO3,HNO2,HCLO4,HMno4.so axit manh la

ngữ văn 8 đây ư

bai nay lop mAY