Ch. 2.4 Chemical Reactions & Enzymes 2T/3T

In chemical reactions, atoms are:

• Created

• Destroyed

• Rearranged

• Neutralized

When hydrogen and oxygen combine to form water, water is

• a product

• a reactant

• an enzyme

• a catalyst

Identify the reactant(s) in the chemical reaction CO₂ + H₂O -->H₂CO₃

• CO₂, H₂O and H₂CO₃

• CO₂ and H₂O

• H₂CO₃

• CO₂

What is the process that changes one set of chemicals into another set of chemicals?

• cohesion

• hydrogen bonding

• chemical reactions

• dissolving

The energy needed to get a reaction started is the

• adhesion energy

• activation energy

• cohesion energy

• chemical energy

Chemical reactions that release energy

• will not occur.

• need catalysts to occur.

• will always explode

• do not always occur spontaneously.

If a reaction in one direction releases energy, the reaction in the opposite direction

• also releases energy.

• absorbs energy.

• destroys energy.

• cannot occur.

Which of the following diagrams shows the reaction pathway of a reaction that absorbs energy?

• 
• 
• 
• 

Which of the following statements about enzymes is NOT true?

• Enzymes work best at a specified pH.

• All enzymes have the same shape as their substrate.

• Enzymes are proteins.

• The shape of an enzyme allows it to do its job.

Which of the following statements is true about catalysts?

• Catalysts slow down the rate of chemical reactions.

• All catalysts are enzymes.

• Catalysts are used up during a chemical reaction.

• Catalysts lower the activation energy of a chemical reaction.