Multiple choice Which of the following equations is balanced? $KNO_3$ $\to$ $KNO_2$ + $O_2$ $2KNO_3$ $\to$ $2KNO_2$ + O $2KNO_3$ $\to$ $KNO_2$ + $2O_2$ $2KNO_3$ $\to$ $2KNO_2$ + $O_2$ Reveal answer Fill a bubble to check yourself D Correct answer Explanation In option (4), number of atoms on both the sides of the equation is the same.