Chemical Reactions II | Chemistry | Quiz

In order for reactants to form products, they have to overcome what barrier?

Activation Energy

Reaction kinetics

Reaction rate

Catalysts
The speed at which reactant molecules form product molecules is known as the _______.

rate of chemical reactions.

collision theory of chemical reactions.

kinetics of chemical reactions.

energy gain of chemical reactions.
Adding energy to chemical reactants will ______.

cause fewer molecular collisions, which slows the reaction down.

cause more molecular collisions, which speeds the reaction up.
Which of the following variables does NOT affect reaction rate ______.

mixing.

concentration.

temperature.

time.
A catalyst speeds a chemical reaction by increasing its activation energy?

true

false
In your new job as chemical engineer, your supervisor asks you to maximize the reaction rate in a chemical plant. The reaction occurs in the liquid phase and already uses a catalyst. Which is the best option to accomplish your assignment?

Increase temperature only

Increase concentration only

Increase temperature and concentration

Decrease temperature and concentration
Using the same chemical reaction from the previous question, consider two test tubes labeled A and B that contain hydrochloric acid solutions with different concentrations. The solution in test tube A is twice as concentrated as the solution in test tube B. Assuming you drop equal amounts of solid magnesium into both test tubes, in which test tube will the reaction occur faster?

Test tube A

Test tube B

Both would be equal.
Now consider that Test tube A and B from the previous question have the same concentration of hydrochloric acid. If you stirred test tube B while adding the magnesium, but did not stir test tube A, in which tube would the reaction occur faster?

Test tube A

Test tube B

Both would be equal.
You are designing a chemical process that will separate hydrogen from ammonia according to the reaction below. To keep the reaction rate as fast as possible, you decide your design needs to include _______.

a catalyst.

a cooler to decrease the temperature.

Neither a nor b

Both a and b