Chemical reactions quiz

What is a chemical reaction?

• A chemical reaction is a process that involves only one chemical substance.

• A chemical reaction is a process that does not involve any change in properties.

• A chemical reaction is a process that leads to the transformation of physical substances.

• A chemical reaction is a process that leads to the transformation of one set of chemical substances to another.

Give an example of a chemical reaction.

• Photosynthesis in plants

• Baking a cake

• Iron rusting

• Water boiling

What are the reactants in a chemical reaction?

• Catalysts used in a chemical reaction

• Substances present at the beginning of a chemical reaction

• Products of a chemical reaction

• Elements formed after a chemical reaction

What are the products in a chemical reaction?

• Substances formed after the reaction

• Initial reactants

• Byproducts of the reaction

• Unrelated compounds

Explain the difference between physical and chemical changes.

• Physical changes are reversible, while chemical changes are not.

• The main difference between physical and chemical changes is that physical changes do not alter the chemical composition of a substance, while chemical changes do.

• Chemical changes only affect the physical properties of a substance.

• Physical changes involve altering the chemical composition of a substance.

How can you tell if a chemical reaction has occurred?

• Hearing a sound

• Smelling a new odor

• Seeing a shadow

• Observing a change in color, formation of a precipitate, evolution of gas, or change in temperature.

What is the Law of Conservation of Mass?

• Matter can be converted into energy in a chemical reaction

• Matter cannot be created or destroyed in a chemical reaction, only rearranged.

• Matter can be destroyed in a chemical reaction

• Matter can be created in a chemical reaction

Why is it important to balance chemical equations?

• To make the equations look more complicated

• To ensure the law of conservation of mass is obeyed.

• To create confusion among students

• To waste time in class

What is a catalyst in a chemical reaction?

• A catalyst is a substance that has no effect on the rate of a chemical reaction.

• A catalyst is a substance that increases the rate of a chemical reaction without being consumed in the process.

• A catalyst is a substance that is consumed in the chemical reaction.

• A catalyst is a substance that decreases the rate of a chemical reaction.

Name three common types of chemical reactions.

• synthesis, decomposition, combustion

• substitution

• oxidation

• ionization