Answer:
Balanced:
CaO + 3C -> CaC2 + CO
2Mg + O2 -> 2MgO
Not Balanced:
Na + H2O -> 2NaOH + H2
4Fe + O2 > 2Fe2O3
Step-by-step explanation:
To check if a chemical equation is balanced or not, you need to check if the equation has the same amount of each element in both sides.
CaO + 3C -> CaC2 + CO
Left:
Ca: 1
O: 1
C: 3
Right:
Ca: 1
O: 1
C:3
Balanced
Na + H2O -> 2NaOH + H2
Left:
Na: 1
H: 2
O: 1
Right:
Na: 2
H: 4
O: 2
Not Balanced