2Al + 3H2SO4 → Al2(SO4)3 + 3H2↑ (1)
Al2O3 + 3H2SO4 → Al2(SO4)3 + 3H2O (2)
\(n_{H_2}=\frac{6,72}{22,4}=0,3\left(mol\right)\)
a) Theo pT1: \(n_{Al}=\frac{2}{3}n_{H_2}=\frac{2}{3}\times0,3=0,2\left(mol\right)\)
\(\Rightarrow m_{Al}=0,2\times27=5,4\left(g\right)\)
\(\Rightarrow m_{Al_2O_3}=15,6-5,4=10,2\left(g\right)\)
b) Theo pT1: \(n_{H_2SO_4}=\frac{3}{2}n_{Al}=\frac{3}{2}\times0,2=0,3\left(mol\right)\)
\(n_{Al_2O_3}=\frac{10,2}{102}=0,1\left(mol\right)\)
Theo pT2: \(n_{H_2SO_4}=3n_{Al_2O_3}=3\times0,1=0,3\left(mol\right)\)
\(\Rightarrow\Sigma n_{H_2SO_4}=0,3+0,3=0,6\left(mol\right)\)
\(\Rightarrow m_{H_2SO_4}=0,6\times98=58,8\left(g\right)\)
c) Theo pT1: \(n_{Al_2\left(SO_4\right)_3}=\frac{1}{2}n_{Al}=\frac{1}{2}\times0,2=0,1\left(mol\right)\)
\(\Rightarrow m_{Al_2\left(SO_4\right)_3}\left(1\right)=0,1\times342=34,2\left(g\right)\)
Theo PT2: \(n_{Al_2\left(SO_4\right)_3}=n_{Al_2O_3}=0,1\left(mol\right)\)
\(\Rightarrow m_{Al_2\left(SO_4\right)_3}\left(2\right)=0,1\times342=34,2\left(g\right)\)
nH2= 6.72/22.4= 0.3 mol
2Al + 3H2SO4 --> Al2(SO4)3 + 3H2
0.2_____0.3________0.1_______0.3
mAl2O3= 15.6 - 0.2*27=10.2g
nAl2O3 = 10.2/102=0.1 mol
Al2O3 + 3H2SO4 --> Al2(SO4)3 + 3H2O
0.1________0.3_______0.1
nH2SO4= 0.3 + 0.3 = 0.6 mol
mH2SO4= 0.6*98=58.8g
nAl2(SO4)3 = 0.1 + 0.1 = 0.2 mol
mAl2(SO4)3 = 0.2*342 = 68.4g
nH2= 6.72/22.4= 0.3 mol
2Al + 3H2SO4 --> Al2(SO4)3 + 3H2
0.2_____0.3________0.1_______0.3
mAl2O3= 15.6 - 0.2*27=10.2g
nAl2O3 = 10.2/102=0.1 mol
Al2O3 + 3H2SO4 --> Al2(SO4)3 + 3H2O
0.1________0.3_______0.1
nH2SO4= 0.3 + 0.3 = 0.6 mol
mH2SO4= 0.6*98=58.8g
nAl2(SO4)3 = 0.1 + 0.1 = 0.2 mol
mAl2(SO4)3 = 0.2*342 = 6.84g
