Answer:
Step-by-step explanation:
NO₂ --> NO + O₂
We need the same number of each atom on both sides of the equation.
There is 1 nitrogen on the left and right sides of the equation. At this point, the nitrogens are balanced on both sides of the equation.
There are 2 oxygens on the left side and a total of 3 oxygens on the right side (1 oxygen in NO and 2 oxygens in O₂). The oxygens are not balanced.
We can place a 2 in front of NO₂ on the left side and 2 in front of NO on the right side. This will give 4 oxygens on the left side and a total of 4 oxygens on the right side.
We also have now 2 nitrogens on the left side and 2 on the right side.
2 NO₂ --> 2 NO + O₂
The equation is balanced with 2 nitrogens and 4 oxygens on both sides of the equation.