What stress would shift the equilibrium position of the following system to the right?
n2o3(g) ⇌ no(g) + no2(g); δh is negative
decreasing the concentration of n2o3
heating the system
adding a catalyst
increasing the concentration of no

Decreasing the concentration of => To the left

Heating the system => To the left

Adding a catalyst  => No change

Increasing the concentration of NO => To the left

Explanation:

We have to analyze each case:

Decreasing the concentration of N2O3

The compound is a reactive. When we remove the concentration of this compound the reaction has to go to the left in order to restore the initial equilibrium.

Heating the system

In this case, the heat (energy) can be considered as a product because it has a negative sign. Therefore, if we add energy the reaction will move to the opposite side. The reactive side

Adding a catalyst

The addition of a catalyst doesn't change the equilibrium of any reaction. The catalyst addition affects the velocity of the reaction but not the equilibrium.

Increasing the concentration of NO

The NO is a product therefore if we increase the concentration of NO will displace the reaction to the opposite side. To the reactants side

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