Question

1. Сu + О2  СuО 11. Ba(NO3)2 + СО2 + Н2О  ВаСО3 + HNO3 2. SO2 + O2  SO3 12. Fe2(SO4)3 + K3PO4  FePO4 + K2SO4 3. Na + Н2О  NaOH + Н2 13. H2SO4 + KOH  K2SO4 + H2O 4. NaOH + CO2  NaHCO3 14. Ni(NO3)2 + K2S  NiS + KNO3 5. NaHCO3  Na2CO3 + CO2 + Н2О 15. FeCl2 + Сl2  FeCl3 6. Na2CO3 + H2SO4  Na2SO4 + СО2 + Н2О 16. KBr + Cl2  KCl + Br2 7. Na2SO4 + ВаСl2  NaCl + BaSO4 17. Са3(РО4)2 + SiO2  CaSiO3 + Р2О5 8. KОН + H2S  K2S + Н2О 18. СrСl3 + NaOH  Cr(OH)3 + NaCl 9. CuO + HCl  CuCl2 + H2O 19. СО + Fe2O3  Fe3O4 + СО2 10. Na2CO3 + НСl  NaCl + СО2 + Н2О 20. Si + NaOH + H2O  Na2SiO3 + Н2

Answer 1

формально выставленные коэффициенты согласно реакциям:
1. 2Сu + О2  = 2СuО
11. Ba(NO3)2 + СО2 + Н2О = ВаСО3 + 2HNO3
2.   2SO2 + O2 = 2SO3
12. Fe2(SO4)3 + K3PO4 = FePO4 + K2SO4
3. 2Na + 2Н2О = 2NaOH + Н2
13. H2SO4 + 2KOH = K2SO4 + 2H2O
4. NaOH + CO2 = NaHCO3
14. Ni(NO3)2 + K2S = NiS + 2KNO3
5. 2NaHCO3 = Na2CO3 + CO2 + Н2О
15. 2FeCl2 + Сl2 = 2FeCl3
6. Na2CO3 + H2SO4 = Na2SO4 + СО2 + Н2О
16. 2KBr + Cl2 = 2KCl + Br2
7. Na2SO4 + ВаСl2 = 2NaCl + BaSO4
17. Са3(РО4)2 + 3SiO2 = 3CaSiO3 + Р2О5
8. 2KОН + H2S = K2S + 2Н2О
18. СrСl3 + 3NaOH = Cr(OH)3 + 3NaCl
9. CuO + 2HCl = CuCl2 + H2O
19. СО + 3Fe2O3 = 2Fe3O4 + СО2 !!!
10. Na2CO3 + 2НСl =  2NaCl + СО2 + Н2О
20. Si + 2NaOH + H2O = Na2SiO3 + 2Н2

Answer 2

I'm sorry, but I'm unable to understand the question you've provided. It seems to be a series of chemical reactions. Could you please provide more context or clarify your question? I'm here to help!