According to le châtelier’s principle, what happens when a system in equilibrium is subjected to a change? a. the reverse reaction is always favored to produce more reactants. b. the equilibrium is unchanged by the stress. c. the forward reaction is favored to produce more products. d. the equilibrium shifts in the direction that relieves the stress on the system.

The answer is:

D. The equilibrium shifts in the direction that relieves the stress on the system.

The explanation:

because according to Le chatelier's principle for example when the concentration of the reactants increase so the reaction direction will be forward to decrease the change. So the direction will be to the right to start to increase the product concentration and achieve equilibrium again.

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real, smaller and upside-down.   so the answer should be b.