Recall:Recall:
A A physical property is a characteristic of a physical property is a characteristic of a substance that helps us to identify it substance that helps us to identify it (colour, texture, density…)(colour, texture, density…)
A chemical property describes the A chemical property describes the behavior of a substance as it becomes behavior of a substance as it becomes a NEW substance.a NEW substance.
Some common chemical properties Some common chemical properties include:include:
Combustibility: describes the ability of a Combustibility: describes the ability of a substance to burnsubstance to burn
Flammable: the substance will burn Flammable: the substance will burn when exposed to a flame.when exposed to a flame.
Light Sensitivity: some substances will Light Sensitivity: some substances will become new substances when they become new substances when they interact with light.interact with light.
What property is described by each What property is described by each of the following statements:of the following statements:
a)a) Water boils at 100Water boils at 100CC
b)b) Alcohol is flammableAlcohol is flammable
b)b) The density of gold is 19.3 g/cmThe density of gold is 19.3 g/cm
b)b) Paper burningPaper burning
Physical
Physical
Chemical
Chemical
Give one physical and one Give one physical and one chemical property of a chemical property of a
marshmallow:marshmallow:
Physical: white, soft, yummyPhysical: white, soft, yummy
Chemical: flammableChemical: flammable
Chemical and Physical Changes:Chemical and Physical Changes:
In a physical change, the substance In a physical change, the substance remains the same (change of state, remains the same (change of state, dissolving)dissolving)
In a chemical change the original In a chemical change the original substance is changed into one or more substance is changed into one or more different substances.different substances.
Chemical Change Clues:Chemical Change Clues:
2.2. Heat or light is given offHeat or light is given off
http://fireworks
Chemical Change Clues:Chemical Change Clues:
3.3. Bubbles of gas are formedBubbles of gas are formed
Chemical Change Clues:Chemical Change Clues:
4.4. A solid material (precipitate) A solid material (precipitate) forms.forms.
** These only suggest a new substances ** These only suggest a new substances has formed, you must consider several has formed, you must consider several clues to determine what type of change clues to determine what type of change has taken place. **has taken place. **
Physical or Chemical Change?Physical or Chemical Change?
1.1. Mixing kool-aid and waterMixing kool-aid and water
2.2. Cloths catching on fireCloths catching on fire
3.3. Water boilingWater boiling
4.4. Cooking muffinsCooking muffins
physical
physical
chemical
chemical
Chemical Property LabChemical Property Lab
Question: What will happen to a dull and Question: What will happen to a dull and dark copper penny when it is put into a dark copper penny when it is put into a bowl of vinegar and salt.bowl of vinegar and salt.
Hypothesis: If you put a dark and dull penny Hypothesis: If you put a dark and dull penny in a salt and vinegar then _____________ in a salt and vinegar then _____________ __________________________________________________________________
Chemical Property LabChemical Property Lab
Apparatus:Apparatus: PennyPenny ¼ cup white vinegar¼ cup white vinegar 1 tsp salt1 tsp salt SpoonSpoon bowlbowl
Chemical Property LabChemical Property Lab
MethodMethod1.1. Record Physical Properties of penny Record Physical Properties of penny
2.2. Mix the vinegar and salt in the bowlMix the vinegar and salt in the bowl
3.3. Dip the penny in the mixture using a spoonDip the penny in the mixture using a spoon
4.4. Wait a few minutes and remove the pennyWait a few minutes and remove the penny
5.5. Record Obervation- Physical Properties of Record Obervation- Physical Properties of penny ( after being dipped)penny ( after being dipped)
Chemical Property LabChemical Property Lab
Physical Properties
Original State of Penny
State of Penny after being dipped
Chemical Property LabChemical Property Lab
Conclusion: explain if your hypothesis was Conclusion: explain if your hypothesis was correct or notcorrect or not
Application: how does this apply to other Application: how does this apply to other areasareas
Hand in: Due Thursday, May 1Hand in: Due Thursday, May 1