Catalyst questions

Which potential energy diagram represents the change in potential energy that occurs when a catalyst is added to a chemical reaction? Refer to the diagrams below.

• Diagram 1

• Diagram 2

• Diagram 3

• Diagram 4

Which phrase describes the effect of adding a catalyst to a chemical reaction in order to increase the reaction rate?

• provides a different reaction pathway with a lower activation energy

• provides a different reaction pathway with a higher activation energy

• uses the same reaction pathway with a higher activation energy

• uses the same reaction pathway with a lower activation energy

A catalyst increases the rate of a chemical reaction by:

• providing an alternate reaction pathway

• providing the required heat of reaction

• increasing the potential energy of the products

• increasing the activation energy of the reaction

Balance equation 1 using the smallest whole-number coefficients.

Explain, in terms of collision theory, why an increase in temperature increases the rate of reaction between methane gas and steam.

State what is represented by interval A on the potential energy diagram.

Determine the number of moles of hydrogen gas required to react completely with 50.0 moles of nitrogen gas in the production of ammonia.

The addition of a catalyst to a chemical reaction provides an alternate pathway that:

• increases the potential energy of reactants

• decreases the potential energy of reactants

• increases the activation energy

• decreases the activation energy

Given the potential energy diagram for a reaction: . Which intervals are affected by the addition of a catalyst?

• (1) 1 and 2

• (2) 1 and 3

• (3) 2 and 4

• (4) 3 and 4

Describe how the catalyst, zymase, speeds up this reaction.