Chemical and Physical Changes in Matter

Physical vs. Chemical Changes

How can Matter change?

Review - Properties of Matter

• We can observe the properties of matter.

• To observe Physical properties, we use our five senses.

• To observe Chemical properties require, we have to change what matter is made of.

Multiple Choice

To observe _____ properties, we do NOT need to change what matter is made of.

• Physical

• Chemical

Multiple Choice

We can observe Size without changing what matter is made of.

Is Size a physical property?

• Yes

• No

Multiple Choice

We can observe Reactivity only if we change what matter is made of.

Is Reactivity a physical property?

• Yes

• No

Multiple Choice

To observe _____ properties, we need to change what matter is made of.

• Physical

• Chemical

Multiple Choice

We can observe Color without changing what matter is made of.

Is Color a chemical property?

• Yes

• No

Multiple Choice

We can observe Flammability only if we change what matter is made of.

Is Flammability a chemical property?

• Yes

• No

Open Ended

I decide if it is a chemical or physical property by asking if I ______.

Physical Changes

• Physical changes affect physical properties.

• Can change size or shape

• Can also change state (solid, liquid, gas)

• What the matter is made of stays the same

Multiple Choice

In a physical change, do we change what matter is made of?

• Yes

• No

Multiple Choice

In a ____ change, we do not change what matter is made of.

• Chemical

• Physical

Multiple Choice

I rip a sheet of paper into pieces. This is a physical change because ____.

• I changed the size or shape

• I changed the state of matter

Multiple Choice

I boiled water on the stove. This is a physical change because ____.

• I changed the size or shape

• I changed the state of matter

Multiple Choice

I made ice cubes in the freezer. This is a physical change because ____.

• I changed the size or shape

• I changed the state of matter

Multiple Choice

I sharpened my pencil. This is a physical change because ____.

• I changed the size or shape

• I changed the state of matter

Open Ended

One example of a physical change is...

Chemical Changes

• Chemical changes produce a new substance

• The matter we start with is different from the matter we ended with

• We cannot undo most chemical reactions

Multiple Choice

In a chemical change, do we change what matter is made of?

• Yes

• No

Multiple Choice

In a ____ change, we change what matter is made of.

• Chemical

• Physical

Multiple Choice

I set wood on fire. This is a chemical change because ___.

• I started with wood and ended with smaller wood

• I started with wood and ended with ash and smoke

Multiple Choice

I bake a cake. This is a chemical change because ___.

• I started with a liquid and ended with a solid

• I started with flour, eggs, and butter and ended with cake

Multiple Choice

A tree does photosynthesis. This is a chemical change because ___.

• It started with sunlight and ended with sugar

• It got bigger

Multiple Choice

A metal pipe rusts. This is a chemical change because ___.

• It started with iron and ended with iron oxide

• It turned brown

Open Ended

One example of a chemical change is ____.

Chemical or Physical?

• Remember, a physical change affects size, shape, or state. It does not change what matter is made of.

• A chemical change makes a new substance.

Multiple Choice

I chew on a lifesaver. The mint breaks in half. This change is ____.

• Chemical

• Physical

Multiple Choice

In my stomach, the mint is broken down to make glucose. This change is ____.

• Chemical

• Physical

Multiple Choice

I put dough in an oven and take our bread. This change is ____.

• Chemical

• Physical

Multiple Choice

I slice the bread into pieces. This change is ____.

• Chemical

• Physical

Open Ended

Wood physically changes when ______.

Wood chemically changes when ______.