T3 Lesson 2 Quiz: Chemical Change

Cutting, melting, bending, or crushing are examples of what kind of change?

• reactant
• product
• physical
• chemical

What kind of change is the formation of rust and ash?

• reactant
• product
• physical
• chemical

Which of the following can occur when a chemical reaction takes place? Choose all that apply.

• New bonds form.
• Existing bonds break.
• New substances form.
• Changes don’t affect matter.

In a chemical change, atoms and molecules rearrange to form new ones. Substances that undergo chemical changes are called __________________________.

• reactants
• products

In a chemical change, atoms and molecules rearrange to form new ones. What these atoms & molecules form are called _________________________.

• reactants
• products

What is the best way to be certain that a chemical reaction has occurred?

• Some bubbles form.
• A color change occurs.
• A new substance forms.
• The materials do not react.

Some chemical reactions need energy in the form of heat to take place, while others give off energy. The temperature after Reaction 1 takes place is _______________ the temperature before the reaction which means this graph represents a ________________ reaction.

• greater than; endothermic
• greater than; exothermic
• less than; exothermic
• less than; endothermic

Some chemical reactions need energy in the form of heat to take place, while others give off energy. Reaction 2 requires an endless source of energy. The temperature after the reaction is _________________ the temperature before the reaction which means Reaction 2 is an ____________________ reaction.

• greater than; endothermic
• greater than; exothermic
• less than; endothermic
• less than; exothermic

Which condition(s) can affect the rate of a chemical reaction?

• surface area
• temperature
• concentration
• catalysts/inhibitors
• all of the answer choices affect the rate of a reaction

The minimum amount of energy needed to start a chemical reaction is called ___________________________.

• activation energy
• solar energy
• chemical energy
• catalyst energy