Physical and Chemical Changes

MATERIALS:

Chalkboard; 1 rusty nail, 1 smooth nail; 1 apple, 1 container apple juice; 1 chunk of wood, 1 chunk of charred wood; corn kernels, popcorn; banana, banana chips; small boxes to put each group of items in; drawing paper, coke bottle, baking soda, vinegar, poster board, bulletin board

SET:

Raise your hand if you look exactly the same today as you did in 1st grade. Think of one way you have changed. Tell your neighbor. (Discuss). You have changed in size, age, etc. But you are still YOU!

Today we will learn about two kinds of changes: Physical change and chemical change.

INSTRUCTION:

(Write the terms on the chalkboard and say together:

PHYSICAL CHANGE and CHEMICAL CHANGE.) A physical change is change in size, shape, or state of matter. Ice that melts is still water, even though it has changed states. That is an example of a physical change.

A chemical change completely changes the object. A nail or tin can will rust. Your bicycle or other metal toy left out in the weather will rust. That is also a chemical change. A piece of paper that burns undergoes a chemical change.

ACTIVE PARTICIPATION:

Divide children into groups of 4. Give each group a different box of items to compare and contrast. Discuss among the group. Each group makes a chart describing the "before" and "after" of the item, and decide if it has undergone a physical or chemical change. Rotate the boxes to all groups.

Suggested items:

1. Apple - apple juice (physical)
2. Chunk of wood - charred wood (chemical)
3. Corn kernels - popcorn (physical)
4. Smooth nail - rusty nail (chemical)
5. Banana - banana chips (physical)
6. Whole sheet of paper - torn pieces of paper (physical)

CLOSURE:

Today, we have learned about physical and chemical changes. On your paper write at least three different items that you know of that have undergone either a physical or chemical change. Use this format:

1. Changed from __________ to __________

ENRICHMENT:

Bring a treat for your classroom either popcorn or banana chips. Enjoy!

SCIENTIST CONNECTION:

Marie Curie was a Polish physicist who discovered the radioactive element radium. Radium is now used to treat the disease. Thanks to the determination of skill and courage of this woman, many cases of cancer can be treated or controlled.

Tennessee Science Curriculum Framework,

http://www.utm.edu/departments/ed/cece/third/3D3.shtml