Chemical Reactions and Energy

Questions and Answers

What is the role of enzymes in chemical reactions?

They convert reactants into products without altering the reactants.

They speed up the reaction by lowering activation energy. (correct)

They provide energy to the reaction.

They increase the temperature of the reaction.

Which of the following correctly describes the difference between endothermic and exothermic reactions?

Endothermic reactions release energy while exothermic absorb energy.

Exothermic reactions are always faster than endothermic reactions.

Endothermic reactions absorb heat while exothermic reactions release heat. (correct)

Exothermic reactions occur without any change in temperature.

What are the building blocks of macromolecules known as?

Polymers

Monomers (correct)

Cells

Compounds

What is a characteristic of lipids?

<p>They do not have real monomers.</p> Signup and view all the answers

What term is used to refer to reactants in enzyme-catalyzed reactions?

<p>Substrates</p> Signup and view all the answers

Study Notes

Chemical Reactions

Reactants are the starting substances in a chemical reaction, while products are the substances formed as a result.
Examples of chemical reactions include the reaction between Coke and Mentos, volcanic eruptions, and the synthesis of mustard gas.

Energy in Chemical Compounds

Energy is stored within the chemical bonds of compounds.

Types of Reactions

Endothermic reactions absorb energy, often resulting in a temperature decrease (cold).
Exothermic reactions release energy, typically causing an increase in temperature (heat).

Role of Enzymes

Enzymes accelerate chemical reactions by lowering the activation energy required for the reaction to occur.
Reactants in an enzyme-catalyzed reaction are referred to as substrates.

Macromolecules

Four main types of macromolecules:
- Carbohydrates: Serve as the primary fuel source for most living organisms, typically composed of monosaccharides.
- Lipids: Serve various functions, are hydrophobic, and do not have distinct monomers; essential for building cell membranes.
- Proteins: Fundamental components of all living organisms, responsible for a vast range of functions.
- Nucleic Acids: Molecules that store, transmit, and express genetic information.

Monomers and Polymers

Monomers are single units that join together to form polymers, which are larger molecules comprised of these repeating units.

Description

Dive into the fascinating world of chemical reactions with this quiz. Explore the roles of reactants and products, understand energy changes, and learn about the influence of enzymes on reaction rates. Test your knowledge on various examples and concepts related to chemistry.