Question

помогите:  Na-->Na2O-->NaOH-->Na2CO-->Na

Answer 1

NaOH +3Na2CO --> NaCO3(p.замещение)

Answer 2

1)4Na+O₂=2Na₂O
2)Na₂O+H₂O=2NaOH
3)NaOH+MgCO₃=Mg(OH)₂+Na₂CO₃
4)Na₂CO₃+H₂=Na+H₂O+CO₂