Chemical Reactions

In a ___________change, a substance changes into a different substance.

• Physical
• Chemical

How many Al atoms are in this compound?         4Al₂O₃

• 2
• 8
• 6
• 4

How many F atoms are in this compound?
6MgF₂ 

• 2
• 6
• 8
• 12

a copper penny turning greenish after a few years.

• Chemical Change
• Physical Change

An gel ice pack getting cold after you put it in the freezer for an hour.

• Chemical Change
• Physical Change

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

• water freezes to form ice

• sugar dissolves in water

• gasoline burns in a car engine

• a piece of metal expands when it is heated

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

• rusting of a bicycle
• painting a house
• washing a dog
• tearing up a newspaper

Which one shows that a chemical reaction has occurred?

• dissolving

• melting

• formation of a gas

• bending

What is the BEST definition of a chemical reaction?

• A change in matter that produces one or more NEW substances

• When two things combine and EXPLODE.

Which part of an atom is POSITIVELY charged?

• protons
• neutrons
• electrons
• atoms