<p>In the reaction: C + O2 --> CO2, carbon is the reducing agent, being oxidized from 0 to +4 while oxygen is the oxidizing agent, being reduced to -2. </p>
<p>So basically it's already balanced. So my question is about the half reaction balancing technique. If a redox reaction is already balanced (in charges) then all one must do to balance the equation is to balance the coefficients correct? However if the charges differ on both sides, then half reaction technique should be utilized?</p>