Answer:
C
Explanation:
Both lithium and oxygen react to form an ionic bond between them. There is one Oxygen atom on the right side and 2 Oxygen atoms on the left, therefore coefficient 2 is added on right side to balance the oxygen atoms.
Li + O2 --> 2 Li2O
There will be 4 Lithium atoms on right side and 1 Lithium on the left therefore coefficient 4 is added to balance the lithium atoms
4 Li + O2 --> 2 Li2O
The balanced equation is:
4 Li + O2 --> 2 Li2O
