When sodium reacts with oxygen, 0.20 mol of sodium (Na\text{Na}Na) reacts with 0.05 mol of oxygen gas (O2\text{O}_2O2).
Which is the correct balanced equation for the reaction?
Na+O2→NaO2\text{Na} + \text{O}_2 \rightarrow \text{NaO}_2Na+O2→NaO2
2Na+O2→Na2O22\text{Na} + \text{O}_2 \rightarrow \text{Na}_2\text{O}_22Na+O2→Na2O2
4Na+O2→2Na2O4\text{Na} + \text{O}_2 \rightarrow 2\text{Na}_2\text{O}4Na+O2→2Na2O
4Na+2O2→2Na2O24\text{Na} + 2\text{O}_2 \rightarrow 2\text{Na}_2\text{O}_24Na+2O2→2Na2O2