Unit 4: Chemical Reactions Pre-Test

What is a chemical reaction?

• A change in color

• A change in temperature

• A process that rearranges atoms to form new substances

• A change in state

Which of the following is an example of a chemical change?

• Ice melting

• Wood burning

• Sugar dissolving in water

• Boiling water

In a chemical equation, what do the coefficients represent?

• Number of atoms

• Number of molecules

• Subscripts

• Phase of matter

What is the purpose of a subscript in a chemical formula?

• It indicates the number of molecules

• It specifies the charge of an ion

• It represents the number of atoms

• It denotes the phase of matter

What is a reactant in a chemical reaction?

• The end product

• The substance that undergoes the reaction

• The catalyst

• The substance formed during the reaction

In a chemical equation, the reactants are written on the:

• Left side

• Right side

• Top

• Bottom

Which of the following is a product in a chemical reaction?

• The starting materials

• The substance that undergoes the reaction

• The end result of the reaction

• The catalyst

In a chemical equation, the products are written on the:

• Left side

• Right side

• Top

• Bottom

Which of the following is NOT a sign of a chemical reaction?

• Formation of a precipitate

• Change in odor

• Change in shape

• Evolution of gas

What does the Law of Conservation of Mass state?

• Mass is created during a chemical reaction

• Mass is destroyed during a chemical reaction

• Mass is conserved in a chemical reaction

• Mass is directly proportional to volume