Physical and Chemical Physical and Chemical ChangesChanges

MatterMatter

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

MatterMatterCan be described as Can be described as

Physical property – description of Physical property – description of substance. Ie. Colour, smell, taste, substance. Ie. Colour, smell, taste, density. density.

Chemical property – Describes how a Chemical property – Describes how a substance reacts when mixed with substance reacts when mixed with other substances. ie. Gas burns in other substances. ie. Gas burns in heat and oxygen. heat and oxygen.

Physical ChangePhysical Change A change that A change that does notdoes not produce a new produce a new

substance. substance.

Usually reversibleUsually reversible

e.g. melting ice, dissolving salte.g. melting ice, dissolving salt

Chemical ChangeChemical Change A reaction takes place creating a new A reaction takes place creating a new

substance.substance.

Usually hard or Usually hard or impossible to impossible to reverse.reverse.

Ex. Cooking an eggEx. Cooking an egg

e.g. Gummy Bear Inferno Demoe.g. Gummy Bear Inferno Demo

Sugar + OSugar + O22 Carbon Dioxide + H Carbon Dioxide + H22OO

In a chemical change, there are clues that a In a chemical change, there are clues that a change occurred. Can you name them? change occurred. Can you name them?

There are 5 clues that a chemical There are 5 clues that a chemical change may have occurred…change may have occurred…

1. A new colour appears.1. A new colour appears.

2. Heat or Light is given off.2. Heat or Light is given off.

3. Bubbles of Gas are formed.3. Bubbles of Gas are formed.

4. A new solid material forms (precipitate).4. A new solid material forms (precipitate).

5. A new odour is made.5. A new odour is made.

What do you think?What do you think?

1. Sugar dissolving in tea?1. Sugar dissolving in tea?2. Breaking water up into 2. Breaking water up into

hydrogen and oxygen gas?hydrogen and oxygen gas?3. Burning a log in a campfire?3. Burning a log in a campfire?4. Crushing an Aspirin?4. Crushing an Aspirin?5. Metal Rusting?5. Metal Rusting?6. Lighter fluid burning?6. Lighter fluid burning?7. An egg rotting? 7. An egg rotting? 8. Boiling water?8. Boiling water?9. Test tubes in picture 9. Test tubes in picture ? ?

Prepping your labsPrepping your labs Write in BLUE or BLACK pen onlyWrite in BLUE or BLACK pen only

Mistakes Mistakes

Observations usually in a table (ruler)Observations usually in a table (ruler)

All titles and subtitles underlined (ruler)All titles and subtitles underlined (ruler)

Date and name in the upper right corner with lab partners Date and name in the upper right corner with lab partners namename

Analysis must be in full sentences. That means include the Analysis must be in full sentences. That means include the question in the answerquestion in the answer

Physical and Chemical Changes LabPhysical and Chemical Changes Lab

PurposePurpose: To collect and use evidence to identify : To collect and use evidence to identify physical and chemical changes. physical and chemical changes.

Materials:Materials: See Ms. Jamieson’s pptSee Ms. Jamieson’s ppt

Procedure:Procedure: See Ms. Jamieson’s ppt See Ms. Jamieson’s ppt

Observations:Observations:

Mar. 21, 2011Mar. 21, 2011

Name: Name: LP: LP:

Before During After

Exp. 1

Exp. 2

Exp. 3

ProcedureProcedure: :

Exp. 1Exp. 1 1. Add 2 cm of HCl to test tube1. Add 2 cm of HCl to test tube

2. Add 2cm strip of Mg. 2. Add 2cm strip of Mg.

3. Dispose & Rinse test tube.3. Dispose & Rinse test tube.

Exp. 2Exp. 2 1. Add 3 cm of distilled water to test tube1. Add 3 cm of distilled water to test tube

2. Add ½ pea size scoop of CuSO2. Add ½ pea size scoop of CuSO44

3. Shake gently (do not put thumb on top)3. Shake gently (do not put thumb on top)

Exp. 3Exp. 3 1. Add pea size ball of steel wool to test tube used in #21. Add pea size ball of steel wool to test tube used in #2

2. Shake gently (do not put thumb on top). 2. Shake gently (do not put thumb on top).

3. Dispose & Rinse test tube.3. Dispose & Rinse test tube.

Exp. 4Exp. 4 1. Add 1cm of HCl to the test tube1. Add 1cm of HCl to the test tube

2. Add 2 drops of phenolthalein. 2. Add 2 drops of phenolthalein.

3. Slowly add drops of NaOH while shaking gently until 3. Slowly add drops of NaOH while shaking gently until you you observe a changeobserve a change

4. Dispose & Rinse test tube.4. Dispose & Rinse test tube.

AnalysisAnalysis: :

1. Classify each of the experiments as chemical or 1. Classify each of the experiments as chemical or physical changes. Write a sentence to justify your physical changes. Write a sentence to justify your decision using specific evidence you’ve observed.decision using specific evidence you’ve observed.

2. Give one example from everyday life of a 2. Give one example from everyday life of a physical change. Explain how to reverse it. physical change. Explain how to reverse it.

3. In your own words, how would you explain the 3. In your own words, how would you explain the difference between a physical and chemical difference between a physical and chemical change to a friend?change to a friend?