Chemical vs. Physical Change

6th Grade

There are two types of properties:

Physical Physical PropertiesProperties

Chemical Chemical PropertiesProperties

Physical Properties can be observed without changingwithout changing the matter:

• shape• state (solid, liquid, or gas)• density• color• smell• appearance

Physical PropertiesPhysical Properties of this ball:

• round shape

• solid• red color

Chemical Properties can only be tested by changingby changing the matter:

• flammability (will it burn?)• oxidation (will it rust?)• volatility (will it explode?)• reactivity (will it react to chemicals?)

Chemical PropertiesChemical Propertiesof this flask:

• not flammablenot flammable• won’t rustwon’t rust

• can explode if can explode if over heatedover heated

• won’t react to acidwon’t react to acid

What are some Physical PropertiesPhysical Properties for this hamburger?

• solid• round bun• many colors• smells tasty

What are some Chemical PropertiesChemical Properties for this hamburger?

• can burn (except lettuce

and pickles)• won’t rust• won’t explode• will react to stomach acid by dissolving

What are some Physical PropertiesPhysical Properties for propane gas?

• gas• no fixed shape• invisible•Smells like rotten eggs• very light density

What are some Chemical PropertiesChemical Properties for propane gas?

• will burn easily• gas won’t rust

(but tank will)• can explode!• can react with

other chemicals

Is it a Physical PropertyPhysical Property or a Chemical PropertyChemical Property?

Strawberriesare red with agreen top.

Physical PropertyPhysical Property! It doesn’t change the strawberry to check its color.

Apples will oxidize andturn brown if left out in air.

Chemical PropertyChemical Property! It will change the apple to wait for it to brown.

Is it a Physical PropertyPhysical Property or a Chemical PropertyChemical Property?

Copper wireconducts electricity

Physical PropertyPhysical Property! It doesn’t change the copper wire to check conductivity.

Is it a Physical PropertyPhysical Property or a Chemical PropertyChemical Property?

Alka Seltzerfizzes in water

Chemical PropertyChemical Property! It will change the Alka Seltzer to dissolve it in water.

Is it a Physical PropertyPhysical Property or a Chemical PropertyChemical Property?

The density of goldis 19.3 g/mL

Physical PropertyPhysical Property! It won’t change the gold to calculate its density.

Is it a Physical PropertyPhysical Property or a Chemical PropertyChemical Property?

Physical Change

• A change that alters the appearance of a material but doesn’t make that material into something new

• Examples:– Tearing Paper– Chopping Wood– Molding Clay– Cutting Hair– Mixing Salt and Pepper

• DOES NOT form a new substance

Chemical Change

• A change in matter that produces a new substance

• Examples:– Fireworks– Food rotting– Lighting a match

5 clues to a Chemical change

1. Color Change2. Gas given off (bubbles)3. Temperature Change (hot or cold)4. Precipitate formed – two liquids

form a solid5. New substance formed

Physical or Chemical Change?

Physical Change

Physical or chemical change?

• Hammering wood together

Physical Change

Physical or chemical Change?

• Rusty Bike

Chemical Change

Physical or Chemical change?

• Melting Butter

Physical Change

Physical or chemical change?

• Rotting food

Chemical Change

Physical or Chemical Change?

• Mixing Kool-Aid powder in water

Physical Change

Physical or chemical change?

• Mowing the grass

Physical Change

Physical or chemical change?

• Bleaching your hair

Chemical Change

Physical or chemical change?

• Fireworks exploding

Chemical Change

Physical or chemical change?

• Squeezing oranges to make orange juice

Physical Change

Physical or chemical change?

• Frying an egg

Chemical Change

Physical or chemical change?

• Burning leaves

Chemical Change

Physical or chemical change?

• Cream being whipped

Physical Change

Physical or chemical change?

• Burnt toast

Chemical Change

Physical or chemical change?

• Melting Ice cream

Physical Change