Question

Which of the following phase diagrams represents how a catalyst is able to change the rate of a reaction? (2 points) A regular exothermic potential energy diagram is shown, with a dotted line representing how the potential energy diagram changes with the use of a catalyst. The dotted line shows a new potential energy diagram with two potential energy hills, instead of the one hill in the regular potential energy diagram. A regular exothermic potential energy diagram is shown, with a dotted line representing how the potential energy diagram changes with the use of a catalyst. The dotted line shows a new potential energy diagram with a taller activation energy hill than that in the original potential energy diagram. A regular exothermic potential energy diagram is shown, with a dotted line representing how the potential energy diagram changes with the use of a catalyst. The dotted line shows a new potential energy diagram with two activation energy hills, the second taller than the first, instead of the one hill in the regular potential energy diagram. A regular exothermic potential energy diagram is shown, with a dotted line representing how the potential energy diagram changes with the use of a catalyst. The dotted line shows a new potential energy diagram with a shorter activation energy hill than that in the original potential energy diagram.

Answer 1

Answer: The dotted line shows a new potential energy diagram with a shorter activation energy hill than that in the original potential energy diagram.

Explanation:

Activation energy is the extra amount of energy required by the reactants to cross the energy barrier to get converted into products.

When a catalyst is added, it lowers down the activation energy which is shown by a dotted line. As now less energy is required,  more of reactants can cross the energy barrier and get converted to products and thus increase the rate of reaction.

A catalyst increases the rate of reaction for both exothermic and endothermic reactions.