Unit 4 Assessment

6.5c: Students can differentiate between elements and compounds on the most basic level.

6.5d: Students can identify the formation of a new substance due to a chemical change.

Guiding Questions

1. What is the difference between elements and compounds?

2. How is chemical change identified?

3. How can scientists determine whether a new substance is formed during a reaction?


physical change - a change in which the properties of a substance change but the identityof the substance always remains the same; a change in the size or state of a substance, usually from temperature, pressure or motion

chemical change - a change in which the identity of a substance changes due to its chemical properties and forms a new substance or substances
element - a substance composed of atoms having an identical number of protons in each nucleus

compound - a substances whose molecules contain atoms from different elements

chemical symbol - a one- or two-letter abbreviation for an element's name (O - oxygen)

chemical formula - a set of symbols that describe the number and kind of elements in a compound (NaCl)
matter - anything that has mass and takes up space
molecule - a particle of matter made up of two or more atoms joined tightly together
physical properties - any characteristic of a substance, such as state, color and volume, that can be observed or measured without changing or attempting to change the material
chemical properties - any characteristic, such as the ability to burn, that allows a substance to change into a new substance with different properties
oxidation - a common form of chemical reaction which is the combination of oxygen with various elements and compounds

tarnish- a thin layer of corrosion that forms over copper, brass, silver, aluminum and other similar metals as their outermost layer undergoes a chemical reaction

rust- corrosion that forms on iron and iron-coated materials as it undergoes a chemical reaction

exothermic- describes a process which RELEASES thermal (heat) energy

endothermic- describes a process which ABSORBS thermal (heat) energy

Important Links

Study Jams: Elements and Compounds
Bite Size Chemistry
Compounds - Chem4Kids
A Closer Look at Physical and Chemical Changes
Evidence of Chemical Changes

In Class Investigations
Hot Pack
Copper from Aluminum
Rotten Egg Gas
Instant Sunshine
Instant Sunshine slow motion

Other Reactions

Awesome Blossom

Color Change Reaction

Sugar Snake

Oxidation Explosion

Underwater Fireworks - Oxidation

Elephant Toothpaste

Orange Sorbet

Sizzling Sunset

Smokescreen On Demand

Surprise Fire

Genie in the Bottle

Interactive Games

Periodic Table Game
Kitchen Chemistry
Chemistry Rags to Riches
Alien Juice Bar (pH and Chemical Change)
Reversible and Irreversible Changes
Physical Vs. Chemical
Chemical Vs. Physical

Journal Entries:


chemical change.JPG