Question

Will give medal! Help me understand this!

The reaction of two gases in a sealed container produces a different gas, and the system reaches equilibrium. What change in concentration would shift the equilibrium to the left?

Decreasing the concentration of either a reactant or the product

Increasing the concentration of either a reactant or the product

Decreasing the concentration of a reactant or increasing the concentration of the product

Increasing the concentration of a reactant or decreasing the concentration of the product

Answer 1

Decreasing the concentration of a reactant or increasing the concentration of the product IS THE RIGHT ANSWER
Le Châtelier’s Principle Says that: If a system at
equilibrium is disturbed by a change in temperature, pressure, or a component concentration, the system will shift its equilibrium position so as to counteract the effect of the disturbance.
So Addition of The Product will make the system consume more of the product and making the reverse reaction happen more likely to get the reactants back. and Decreasing the concentration of the reactants is going to make the system consume more of the products to compensate the loss of the reactants.
I hope you understand me and if you don't text me. Okay ^-^

Answer 2

A decrease in concentration of reactant will shift equation to the left.
For your understanding:
IMAGINE, if you have something(reactant) missing on the left, you will need another something to replace it ASAP and the product on the right will attempt to do so.