Дано
n(HF)= 0.5 mol
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m(HF)-?
M(HF) = 1+19=20 g/mol
m(HF) = n(HF)*M(HF) = 0.5*20 = 10 g
ответ 10 г
1. CO2+H2O=H2CO3
2. 2Al+Fe2O3=Al2O3+2Fe
3. 2Fe(OH)3=Fe2O3+3H2O
4. Na2SO4+BaCl2=2NaCl+BaSO4
5. CO2+2Mg=2MgO+C
6. 2H2S+3O2=2SO2+2H2O
7. 2C4H10+9O2=8CO2+10H2O
8. 4CH5N+9O2=4CO2+10H2O+2N2
9. Zn+2HCl=ZnCl2+H2
10. 2CuOH=Cu2O+H2O
1) М (FeO) = 56 + 16 = 72
2) Fe2O3 = 112 + 48 = 160
3) Fe3O4 = 168 + 64 = 232
3) FeS2 = 56 + 64 = 120
4) H2SO4 = 2 + 32 + 64 = 98
5) H3PO4 = 3 + 31 + 64 = 98
6) Cu(OH)2 = 64 + ( 2+ 32) = 98
m(NaCl)=600*0,009=5,4гр.;m(H2O)=600-5,4=594,6гр.;V(H2O)=594,6гр.:1гр./мл=594,6мл
1 - отв:А,
FeCl₃ + 3KOH = Fe(OH)₃↓ +3KCl
Fe³⁺ + 3Cl⁻ + 3K⁺ +3OH⁻ = Fe(OH)₃↓ + 3K⁺ + 3Cl⁻
Fe³⁺ +3OH⁻ = Fe(OH)₃
2 -отв:Б Г
K₂S + 2HCl = 2KCl + H₂S↑
2K⁺ + S²⁻ + 2H⁺ + 2Cl⁻ = 2K⁺ + 2Cl⁻ + H₂S↑
2H⁺ + S²⁻ =H₂S↑
Na₂S + H₂SO₄ = H₂S↑ + Na₂SO₄
2Na⁺ + S²⁻ + 2H⁺ + SO₄²⁻ = H₂S↑ + 2Na⁺ + SO₄²⁻
2H⁺ + S²⁻ = H₂S↑
3 -отв:A, Г
FeSO₄ + 2NaOH = Fe(OH)₂↓ + Na₂SO₄
Fe²⁺ + SO₄²⁻ + 2Na⁺ + 2OH⁻ = Fe(OH)₂↓ + 2Na⁺ + SO₄²⁻
Fe²⁺ + 2OH⁻ = Fe(OH)₂↓
FeCl₂ + 2NaOH = Fe(OH)₂ ↓ + 2NaCl
Fe²⁺ + 2Cl⁻ + 2Na⁺ + 2OH⁻ = Fe(OH)₂↓ + 2Na⁺ + 2Cl⁻
Fe²⁺ + 2OH⁻ = Fe(OH)₂↓
4 -отв:Б