Answer: Chemical equation for the overall reaction obtained by adding these three given equations is:
![2NO_2(g)\rightarrow N_2O_4(g)](https://img.qammunity.org/2020/formulas/chemistry/middle-school/tmzjt8vymybz8hgth3nvcomzm4ci06q175.png)
Step-by-step explanation:
...(1)
...(2)
...(3)
If the same compounds is on same sides in the reactions then add them.
If the same compound is on different sides of the reaction then subtract.
Adding (1) and (2)
![2NO_2(g)+2NO(g)\rightarrow 2NO(g)+O_2(g)+N_2(g)+O_2(g)](https://img.qammunity.org/2020/formulas/chemistry/middle-school/4zd0oybs1z76qg3nvqjh3xg90sqnqy1fa0.png)
NO is present on both sides, which means it will get cancel out.
is on same side it will get added up.
..(4)
Similarly, on adding (3) in (4) we get:
![2NO_2(g)\rightarrow N_2O_4(g)](https://img.qammunity.org/2020/formulas/chemistry/middle-school/tmzjt8vymybz8hgth3nvcomzm4ci06q175.png)
Above equation is obtained by adding given three equations.