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Properties of Matter
MSFWBAT:• differentiate among element, compound, homo- and
hetero-genous mixtures• describe the arrangement and distances among
particles in the solid, liquid, and gas state• differentiate between chemically bonded and
physically blended
Drill – 9/27
• What is matter?• What are the phases of matter?
MatterHas mass and Takes up space
Can only be Separated Chemically, uniform and definite composition
Can be separatedPhysically, not definitecomposition
cannot be Separated intoSimpler substance
Contains two Or more elements
Uniform throughout
Not uniformthroughout
WS:
Gas
assumes the shape and volume of its container
particles can move past one another
compressible -lots of free space between particles
flows easily particles can move past one another
Liquid
assumes the shape of the part of the container which it occupies
particles can move/slide past one another
not easily compressible little free space between particles
flows easily particles can move/slide past one another
Solid
retains a fixed volume and shape rigid - particles locked into place
not easily compressible little free space between particles
does not flow easily rigid - particles cannot move/slide past one another
States of Matter
Deposition
Drill 9.28
• What factor(s) dictate what particular phase a substance exists in?
• 1. temperature (which is relative speed of particles of the substance)
• 2. pressure • 3. distance between particles (can be related to
pressure, but is not the same thing here)• Any change to these variables can (theoretically)
cause a phase change in any kind of matter
9.28
• a. distinguish between physical and chemical properties
• b. contrast physical and chemical changes• c. use law of cons of mass and energy to prove
that mass remains constant during both physical and chemical changes
Physical & Chemical Properties!
• Physical properties: Do not change the chemical nature of matter
• Chemical properties: Do change the chemical nature of matter
Properties of Matter• Physical Properties– Characteristics of a substance that can be observed or
measured without changing the substance’s composition
– Types of Physical Properties:color solubility mass magnetismodor hardness densitymelting point electrical conductivityboiling point
Properties of Matter• Chemical Properties– describe chemical changes of a substance
– Types of Chemical Propertiesrust rot decomposeferment grow
Classify the following as chemical or physical properties
• Freezing point• Leaves rot• A nail rusts• Water turns to steam• Something dissolves• It explodes• Reacts to form a gas• Try some more on the next slide
• It reacts to form carbon dioxide• It smells bad• It is shiny• It is cut in half• Tastes sweet• A candle melts• A balloon is blown up with air• It burns• Red color
Physical & Chemical Changes
• In a physical change, nothing new is created, the matter has just changed to another phase, separated or combined.
• In a chemical change, the substances are altered chemically and display different physical and chemical properties after the change.
Changes in MatterPhysical Changes
- changes which do not alter the identity of a substance
Types of Physical Changescrush or tear
changes in state (between solid/liquid/gas)
Changes in Matter
Chemical Changes- changes (reactions) which alter the identity of a substance
**After a chemical change occurs a new substance is formed**
Types of Chemical Changesburning cooking
chemical reaction with another substance
Physical Separations
• Predict how to separate each of the following heterogeneous mixtures:– Salt and pepper– Sand and iron filings– Mud (dirt from the water)– Fruit salad (the different types of fruit)
Focusing questions
• Indicate if the following are physical or chemical changes:
1. Wood burning2. Plants growing3. Cutting paper4. Ice melting
• “Separate This” WS
Techniques for Physical Separations
• Filtration• Evaporation• Centrifugation• Chromatography• Decantation• Crystallization• Distillation
Filtration Evaporation Centrifugation Chromatography Decantation Crystallization Distillation
Filtration
• A mixture is poured into a funnel fitted with a piece of filter paper.
• Used for beer production and tap water (to remove solid impurities)
Evaporation
• A homogenous mixture is heated so that the water evaporates and just leaves the solid behind
Centrifugation• Really fast spinning
forces the solid or denser substance to the bottom of a sample
Chromatography• A mixture is allowed to move along a fixed
material. The components of the mixture move at different speeds (based on their attraction to the solvent and the material) and so they separate from each other.
Decantation• Let the solid settle and then
pour off the liquid, using something to block the solid
Crystallization
• The process of forming crystals. Used to separate solids from solution.
DistillationWhen a solution is heated, the liquid with a lower boiling point evaporates. The hot vapor that formed can be condensed back to liquid again on a cold surface. EVAPORATION + CONDENSATION
Chemical Separations
• Electrolysis• Chemical Reactions• Decomposition
ElectrolysisUsing electric current to force a chemical reaction with a separation occurring at the electrodes
Focusing question
• How would you separate a mixture of salt, sand, iron filings, ethanol and water into each of the components?
Law of Conservation of Matter and Energy
• Matter and energy cannot be created nor destroyed, only changed in form.
Energy
• Energy is the capacity to do work or to produce heat
• Forms of Energy
– Potential – stored energy– Kinetic – energy of motion
Measuring EnergyA calorie is the amount of heat needed to raise the temperature of 1 gram of water by 1 Celsius degree
1 cal = 1 gram x 1 C0
The SI unit of energy is the joule (J)
1 cal = 4.184 J