nHCl=0,3.2=0,6(mol)

a) PTHH: CuO +2 HCl -> CuCl2 + H2O

0,3_______________0,6___0,3(mol)

b) mCuO=0,3.80=24(g)

c) VddCuCl2=VddHCl=0,3(l)

=>CMddCuCl2=0,3/0,3=1(M)

d) m(muối)=0,3.135=40,5(g)

a)

$Al_2O_3 + 6HCl \to 2AlCl_3 + 3H_2O$

b)

n HCl = 0,4.1,5 = 0,6(mol)

n Al2O3 = 1/6 n HCl = 0,1(mol) => m = 0,1.102 = 10,2(gam)

n AlCl3 = 1/3 n HCl = 0,2(mol) => CM AlCl3 = 0,2/0,4 = 0,5M

nHCl = 0.4*1.5 = 0.6 (mol) 

\(Al_2O_3+6HCl\rightarrow2AlCl_3+3H_2O\)

nAlCl3 = 0.6*2/6 = 0.2 (mol) 

mAlCl3 = 0.2*133.5 = 26.7 (g) 

CM AlCl3 = 0.2/0.4 = 0.5 (M) 

\(n_{H_2SO_4}=0,4\cdot1=0,4mol\)

\(2NaOH+H_2SO_4\rightarrow Na_2SO_4+H_2O\)

 0,8              0,4

\(V_{NaOH}=\dfrac{0,8}{0,5}=1,6l\)

\(n_{H_2SO_4}=0.4\cdot1=0.4\left(mol\right)\)

\(2NaOH+H_2SO_4\rightarrow Na_2SO_4+2H_2O\)

\(0.8.............0.4..............0.4\)

\(V_{dd_{NaOH}}=\dfrac{0.8}{0.5}=1.6\left(l\right)\)

\(V_{dd}=0.4+1.6=2\left(l\right)\)

\(C_{M_{Na_2SO_4}}=\dfrac{0.4}{2}=0.2\left(M\right)\)

Ta có: \(n_{H_2}=\dfrac{6,72}{22,4}=0,3\left(mol\right)\)

a. PTHH: \(Zn+H_2SO_4--->ZnSO_4+H_2\uparrow\left(1\right)\)

b. Theo PT₍₁₎: \(n_{Zn}=n_{H_2}=0,3\left(mol\right)\)

\(\Rightarrow m_{Zn}=65.0,3=19,5\left(g\right)\)

c. Theo PT₍₁₎: \(n_{H_2SO_4}=n_{Zn}=0,3\left(mol\right)\)

Đổi 300ml = 0,3 lít

\(\Rightarrow C_{M_{H_2SO_4}}=\dfrac{0,3}{0,3}=1M\)

d. PTHH: \(2NaOH+H_2SO_4--->Na_2SO_4+2H_2O\left(2\right)\)

Theo PT₍₂₎: \(n_{NaOH}=2.n_{H_2SO_4}=2.0,3=0,6\left(mol\right)\)

\(\Rightarrow m_{NaOH}=0,6.40=24\left(g\right)\)

\(\Rightarrow m_{dd_{NaOH}}=\dfrac{24.100\%}{20\%}=120\left(g\right)\)

a)nMgO=0,15(mol)

Ta có PTHH:

MgO+H2SO4->MgSO4+H2O

0,15......0,15...........0,15..................(mol)

Theo PTHH:mH2SO4=0,15.98=14,7g

b)Ta có:mddH2SO4=1,2.50=60(g)

=>Nồng độ % dd H2SO4là:

C%ddH2SO4=\(\dfrac{14,7}{60}100\)=24,5%

c)Theo PTHH:mMgSO4=0,15.120=18(g)

Khối lượng dd sau pư là:

mddsau=6+60=66(g)

Vậy nồng độ % dd sau pư là:

C%ddsau=\(\dfrac{18}{66}.100\)=27,27%

\(n_{Al}=\dfrac{10,8}{27}=0,4(mol)\\ a,2Al+3H_2SO_4\to Al_2(SO_4)_3+3H_2\\ \Rightarrow n_{H_2}=n_{H_2SO_4}=0,6(mol);n_{Al_2(SO_4)_3}=0,2(mol)\\ b,V_{H_2}=0,6.22,4=13,44(l)\\ c,m_{dd_{H_2SO_4}}=\dfrac{0,6.98}{9,8\%}=600(g)\\ \Rightarrow C\%_{Al_2(SO_4)_3}=\dfrac{0,2.342}{10,8+600-0,6.2}.100\%=11,22\%\)

a) \(n_{Al}=\dfrac{m}{M}=\dfrac{10,8}{27}=0,4\left(\text{mol}\right)\)

Phương trình hóa học phản ứng

2Al + 3H₂SO₄ ---> Al₂(SO₄)₃ + 3H₂

_{2          :   3                   : 1               : 3} 

0,4        0,6            0,2             0,6

mol       mol           mol             mol

Thể tích khí H₂ sinh ra là 

\(V=n.22,4=0,6.22,4=13,44\left(l\right)\)

\(m_{Al_2\left(SO_4\right)_3}=n.M=0,2.342=68,4\left(g\right)\)

\(m_{H_2SO4}=n.M=0,6.98=58,8\left(g\right)\)

\(m_{H_2}=n.M=0,6.2=1,2\left(g\right)\)

=> \(m_{ddH_2SO_4}=\dfrac{m_{H_2SO_4}.100\%}{C\%}=\dfrac{58,8.100\%}{9,8\%}=600\)(g)

=> \(m_{\text{dd sau pư}}=m_{ddH_2SO_4}+m_{Al}-m_{H_2}\)

= 600 + 10,8 - 1,2 (g) = 609,6 (g) 

=> \(C\%_{Al_2\left(SO_4\right)_3}=\dfrac{m_{Al_2\left(SO_4\right)_3}}{m_{\text{dd sau pư}}}.100\%=\dfrac{68,4}{609,6}.100\%\)=11,22%

\(A.Fe+2HCl\rightarrow FeCl_2+H_2\\ B.n_{Fe}=\dfrac{11,2}{56}=0,2mol\\ n_{FeCl_2}=n_{Fe}=0,2mol\\ C_{M_{FeCl_2}}=\dfrac{0,2}{0,1}=2M\\ C.n_{HCl}=2.0,2=0,4mol\\ C_{M_{HCl}}=\dfrac{0,4}{0,1}=4M\)