2nd Six Weeks Review

How many atoms of sodium (Na) are in one molecule of baking soda?

• 1

• 2

• 3

• 4

How many atoms make up one molecule of laughing gas?

• 1

• 2

• 3

• 4

What is a product?

• The starting substance
• The ending substance

What is a reactant?

• The starting substance
• The ending substance

Using the following chemical reaction
Hydrogen + Oxygen --> water
Identify the reactant(s).

• Hydrogen and Oxygen
• water

Using the following chemical reaction
Hydrogen + Oxygen --> water
Identify the product(s).

• Hydrogen and oxygen
• water

Burning is always a chemical reaction.

• True
• false

Which of the following is a chemical reaction?

• Burning bread in the toaster.
• melting wax in a microwave.
• dissolving salt in water
• boiling water to make steam.

Which is a chemical change?

• Melting ice

• A candle burning

• Boiling water

• frost forming inside the freezer

Which of the following indicate that a chemical reaction has occurred?

• The formation of gas bubbles

• An odor

• a change in color

• all of these indicate a chemical reaction