Download Physical Properties Chemical Properties

Chemical Properties
Physical Science
Questions, Questions, Questions…
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On a piece of paper, write down one question you have
about or would like to have answered within the context
of CHEMISTRY!!!
When your done, crumple up the paper into a ball and
hold onto it until you get further instructions!
Back to the Basics
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Matter – anything that has mass and volume
Substance – type of matter with a constant composition
and can be identified by a chemical symbol or chemical
formula and distinct properties.
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Element – any substance made up of only one type of
atom
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Water, Salt, Aluminum
Oxygen, Helium, Iron
Compound – a substance in which two or more elements
are combined
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Chlorine Gas + Sodium metal = Sodium Chloride (salt)
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Cl2
+
Na
=
NaCl
Element
vs.
Compound
The Chemistry Behind the Science Fair
Project Volcano

What do you notice happening when you mix baking soda
and vinegar together??
Chemical Properties
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Describes a specific chemical change that alters the
composition of a substance
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Reactivity
Flammability
Light Exposure
Chemical Changes
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Any change that results in the formation of new
substances
Examples:
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Combustion – combines with oxygen and burns
Corrosion – weakening/discoloration of metals
Oxidation – substances combine with oxygen
In all examples… the key is that there is a formation of a
new material!
Indications of Chemical Change
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Gas Formation (Bubbles/Vapors)
Temperature Change
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Formation of a precipitate
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Endothermic – Energy is absorbed; temperature decreases
Exothermic – Energy is released; temperature increases
Precipitate – solid that forms when two liquids are mixed
Light Energy
Color Change
Something to think about…
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Ever bite into an apple… then leave it on the counter and
come back to it later and it looks like this??

Why do you think this happened?
Elephant Toothpaste…
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She said what?????
Reaction
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2 H2O2(aq) --> 2 H2O(l) + O2(g)
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Let’s take a look!!
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Is this reaction Endothermic or
Exothermic
Physical Science 9/22
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Warm-up
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What is the difference between a Physical Property and a
Chemical property?
Give an example of a Physical Property
Give an example of a Chemical Property
What is an example of a Chemical Change?
Test back – turn into me if you want to retest!
Mini Quiz tomorrow!!
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Chemical changes and properties
Revisiting yesterday…
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Think of what you started with (the reactants)
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List some of the Physical properties of your starting materials
Think of what you ended with (the product)
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List some of the Physical properties of you final material
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How would you identify that a chemical change occurred
in this activity?
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What are some Physical properties of your final product?
Chemical properties?
What you couldn’t see…
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Casein – protein in milk
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Acetic Acid - vinegar
Being able to distinguish between the two…
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As we have seen, there is a difference between physical
and chemical properties. Lets generate a list…
Physical Properties
Chemical Properties
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There is also a difference between physical and chemical
changes. Lets generate another list…
Physical Change
Chemical Change
Class work…
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In your packets, work on the last 4 pages
This is help prepare you for your quiz tomorrow!