The addition of a catalyst in a chemical reaction
(A) increases the concentration of products at equilibrium.
(B) increases the fraction of reactant molecules with a given kinetic energy.
(C) provides an alternate path with different activation energy.
(D) lowers the enthalpy change in the overall reaction.
Lil bro consult your notes ...FYI The answer is C. But do you understand why. There's more to it than simply "lowering the activation energy". Chemical reactions usually occur in multiple steps that together represent the "reaction pathway".
A catalyst allows for a different reaction to occur in this reaction pathway. This new reaction has lower activation energy than the steps in the uncatalyzed reaction. Since the activation energy is lower, more molecules can collide with the needed energy to react and the reaction goes faster.
Therefore, a better way to explain the action of a catalyst is, "A catalyst provides an alternate reaction pathway with a lower activation energy, and an increase in reaction rate."
The correct answer is (C) provides an alternate path with different activation energy.
A catalyst is a substance that speeds up the rate of a chemical reaction without being consumed itself. It works by providing an alternate reaction pathway with a lower activation energy. Activation energy is the minimum energy required for a reaction to occur. By providing an alternate pathway with a lower activation energy, a catalyst allows the reaction to proceed more quickly, effectively lowering the barrier for the reaction to occur. This is why a catalyst can increase the rate of a reaction.
The correct answer is (C) provides an alternate path with different activation energy.
When a catalyst is added to a chemical reaction, it increases the rate at which the reaction occurs. This is because a catalyst provides an alternative pathway for the reaction to proceed, which has a lower activation energy compared to the uncatalyzed reaction.
Activation energy is the energy required for a reaction to proceed. By providing an alternative pathway with a lower activation energy, a catalyst allows more reactant molecules to possess enough kinetic energy to overcome the energy barrier and react.
The concentration of products at equilibrium (option A) is not affected by the addition of a catalyst. A catalyst only enhances the rate of the reaction, but it does not change the position of the equilibrium. The equilibrium concentrations depend on factors like the reaction stoichiometry, initial concentrations, and temperature.
Similarly, the addition of a catalyst does not directly increase the fraction of reactant molecules with a given kinetic energy (option B). It only provides an alternative reaction pathway, thereby increasing the chances of successful collisions between reactant molecules.
Lastly, the addition of a catalyst does not lower the enthalpy change in the overall reaction (option D). The enthalpy change remains the same whether or not a catalyst is present. The catalyst only affects the rate at which the reaction proceeds, not the overall energy change.