Chemistry · Chemical Equilibrium
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The formation of NH3 is a reversible and exothermic process, what will happen on cooling?
- A
More reactant will form
- B
More N2 will be formed
- C
More H2 will be formed
- D
More product (NH3) will be formed
According to Le Chatelier's principle, when a system at equilibrium is subjected to a change in temperature, pressure, or concentration of reactants or products, the equilibrium shifts in a direction that tends to counteract the imposed change.
In the given scenario, the formation of NH3 is exothermic, meaning that heat is released when NH3 is formed. If the reaction mixture is cooled, the equilibrium will shift in the direction that releases more heat. Thus, the equilibrium will shift towards the forward direction (towards the formation of (NH3) to counteract the decrease in temperature. Therefore, more NH3 will be formed.
Hence, the correct option is D) More product (NH3) will be formed.
This option is incorrect.
According to Le Chatelier's principle, when a system at equilibrium is subjected to a change in temperature, pressure, or concentration of reactants or products, the equilibrium shifts in a direction that tends to counteract the imposed change.
Cooling the reaction will cause the equilibrium to shift towards the side of the reactants. However, since the formation of NH3 involves both N2 and H2, it's not accurate to say that more N2 alone will be formed.
Similarly to option (b), cooling the reaction will favor the formation of reactants. However, it's important to note that the reaction involves both N2 and H2, so it's not accurate to say that more H2 alone will be formed.
According to Le Chatelier's principle, when a system at equilibrium is subjected to a change in temperature, pressure, or concentration of reactants or products, the equilibrium shifts in a direction that tends to counteract the imposed change.
In the given scenario, the formation of NH3 is exothermic, meaning that heat is released when NH3 is formed. If the reaction mixture is cooled, the equilibrium will shift in the direction that releases more heat. Thus, the equilibrium will shift towards the forward direction (towards the formation of (NH3) to counteract the decrease in temperature. Therefore, more NH3 will be formed.
Hence, the correct option is D) More product (NH3) will be formed.
Tagged under Chemistry · Chemical Equilibrium · 2012