Chemical Reactions

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

• Physical
• Chemical

The Law of Conservation of Mass states

• that matter exists in all states and reacts the same
• that matter can only be changed into new substances by introducing a catalyst
• that matter exists in the same state throughout any chemical change
• that matter cannot be created or destroyed and that the mass of the products must equal the mass of the reactants

How many F atoms are in this compound?
6MgF₂ 

• 2
• 6
• 8
• 12

How many Al atoms are in this compound?         4Al₂O₃

• 2
• 8
• 6
• 4

A substance that is formed as the result of a chemical reaction is a __________________

• Product

• Reactant

• Starters

• Enders

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

Which of the following IS a physical change?

• Getting a haircut
• Rusty metal
• sour milk
• A compound

A number in front of a chemical formula in an equation that indicates how many molecules or atoms of each reactant and product are involved in a reaction.

• Coefficient
• reactant
• subscript
• product 

What type of reaction is illustrated below?
2HI --> H₂  +  I₂

• synthesis
• decomposition
• single replacement
• double replacement