Question

For the reaction at equilibrium: 2 NO (g) + O2 (g) = 2 NO2 (g) which change will increase the amount of NO2(g)?
1) add NO gas
2) remove NO gas
3) add a catalyst
4) remove O2 gas
5) add NO2 gas

Answer 1

Answer is: 1) add NO gas.
According to Le Chatelier's Principle the position of equilibrium moves to counteract the change, the position of equilibrium will move so that the concentration of nitrogen(II) oxide decreases again by reacting it with oxygen and than concetration of nitrogen (IV) increases.