Physical & Chemical Changes Review

Vocabulary

100

Anything that has mass (weight) and takes up space.

What is MATTER?

200

These are the characteristics of an object that you use your senses to identify.

What are PHYSICAL PROPERTIES?

300

Type of change where a new substance is created.

What is a CHEMICAL CHANGE?

400

A type of change where the substance stays the same, but size and shape may change.

What is a PHYSICAL CHANGE?

500

This type of matter keeps a definite shape.

What is a SOLID?

Physical Change

100

Is a melted popsicle an example of a physical change?

What is YES? You can melt and refreeze a popsicle and it will still be a popsicle.

200

Is Alka-Seltzer and water an example of a physical change?

What is NO? When you mix Alka-Seltzer and water, bubbles form, which indicates a chemical change as taken place.

300

Which food can be separated by physical means: salad or brownies

What is SALAD?

400

Explain how water could be an example of a physical change.

What is freezing and melting water to and from ice is an example of a physical change?

500

Explain how iron fillings and sand can be separated using physical properties.

What is iron is magnetic and sand is not, so you can use a magnetic wand to separate the two substances?

Chemical Change

100

Is rust an example of a chemical change?

What is YES? Rust is a new substance; therefore, it is a chemical change.

200

Name two indicators of a chemical change.

What are formation of a precipitate and bubbles forming without an external heat source.

Also - new odor, new taste, formation of any new substance, temperature change without adding or taking away heat, etc.

300

Which food is an example of a chemical change: trail mix or cake

What is a cake, because you cannot turn a cake back into the eggs, flour, sugar, etc. that you mixed together?

400

True or False. Turning peanuts to peanut butter is an chemical change.

What is FALSE? To make peanut butter, you grind up roasted peanuts, so nothing new is being created.

500

What type of change happens when leaves change color and what is responsible for the change?

What is CHEMICAL? The chlorophyll drains from the leaf and the true colors are shown. The chemical composition of the leaf has changed.

Matter

100

Name the 3 types of matter.

What are SOLID, LIQUID, GAS?

200

The substance that all matter is made of

What are atoms?

300

A solid that is produced as a result of a chemical reaction between two liquids

What is a PRECIPITATE?

400

The chemical reaction makes fireflies glow

What is a BIOLUMINESCENCE?

500

The Law of the Conservation of Matter

What is MATTER CANNOT BE CREATED OR DESTROYED, IT CAN ONLY BE REARRANGED INTO NEW SUBSTANCES?

Chemical Equations

100

What are the substances called to the left of the arrow in a chemical reaction?

6CO2 + 6H2O → C6H12O6 + 6O2

What are PRODUCTS?

200

The arrow in a chemical equation means...

What is 'YIELDS'?

300

What are the substances called to the right of the arrow in a chemical reaction?

6CO₂ + 6H₂O → C₆H₁₂O₆ + 6O₂

What are PRODUCTS?

400

What does the 5 represent in the following chemical equation? Give the name and what it is the number of.

4P + 5O₂ → P₄ + O₁₀

What is COEFFICIENT and it equals the NUMBER OF MOLECULES.

500

Is the following equation balanced? If not, how would you balance it?

CH₄ + 2O₂ → CO₂ + H₂O

What is UNBALANCED? No, to balance the equation I would need to add a coefficient of '2' in front the H₂0 product:

CH₄ + 2O₂ → CO₂ + 2H₂O