Lithium and oxygen react to form lithium oxide. what is the balanced equation for this reaction?

Lithium is Li 
Oxygen gas is O2 
Lithium oxide is Li2O 
Unbalanced Equation is Li + O2 --> Li2O 
There's one O on right side, 2 Os on left, so make coefficient 2 on right side to balance the oxygens. 
Li + O2 --> 2 Li2O 
Now balance the lithiums. There are 4 Lis on right side; 1 Li on left, so make Li coefficient 4 to balance the lithiums. 
4 Li + O2 --> 2 Li2O 
This equation is now fully balanced. 
Therefore balanced equation is: 

4 Li + O2 --> 2 Li2O

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