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• Matter – anything that has mass and takes up space
• Mass- amount of matter an object contains
• Materials – differ in type of matter they are composed of
The Properties of MatterThe Properties of Matter
• Extensive properties – depend on the amount of matter that is present– Example – volume, mass, amount of energy
in the substance
• Intensive properties – do not depend on the amount of matter that is present– Example – melting point, boiling point, density
• Substance – matter that is uniform and Substance – matter that is uniform and has a definite compositionhas a definite composition– All samples of an identical substance have All samples of an identical substance have
the identical physical and chemical the identical physical and chemical propertiesproperties
Physical property Physical property – quality or condition of a – quality or condition of a substance that can be observed or measured substance that can be observed or measured without changing the substance’s without changing the substance’s compositioncomposition
When a substance undergoes a physical change, its physical appearance changes.
Ice melts: a solid is converted into a liquid.
Physical changes DO NOT result in a change of composition.
Properties of Matter
Examples of Physical Properties
Color Odor Hardness Density Solubility Melting point, boiling point, freezing
point Physical state – solid, liquid, gas
States of Matter
Matter can be a gas, a liquid, or a solid.
Gases have no fixed shape or volume.
Gases can be compressed to form liquids.
Liquids have no shape, but they do have a volume.
Solids are rigid and have a definite shape and volume.
Classification of MatterClassification of Matter
Gas and vapor not the same
Gas – normally exists that way at room temperature
Vapor – gas state of a substance that is normally a liquid or solid at room temperature
Physical change
• A change which alters a material without changing its composition
• Cutting, grinding, melting, boiling, freezing, dissolving
Mixtures
Physical blend of two or more substances
Composition can vary
2 types:
Heterogeneous
Homogeneous
Heterogeneous Mixture
Not uniform in composition
Has 2 or more phases
Phase – any part of a system with uniform composition and properties
Dirt, salad, paper, rocky road ice cream
Homogeneous MixtureHomogeneous Mixture
Has a completely uniform Has a completely uniform composition composition
All components are evenly All components are evenly distributeddistributed
Consists of a single phaseConsists of a single phaseCalled a SOLUTIONCalled a SOLUTION
Solution – what do you think of?Solution – what do you think of?
• Can be gas, liquid, or solid!!!!!
Separating mixturesSeparating mixtures
Use PHYSICAL methodsUse PHYSICAL methods Magnet, sifting, Magnet, sifting, Liquid mixtures – distillation Liquid mixtures – distillation
Page 47Page 47
Substances
Can be elements or compounds
Element – definitionCompound – 2 or more elements that
have been CHEMICALLY combined.Can only be separated by CHEMICAL
means
Properties of compoundsProperties of compounds
MUCH DIFFERENT THAN THE MUCH DIFFERENT THAN THE PROPERTIES OF THE ELEMENTS PROPERTIES OF THE ELEMENTS FROM WHICH THEY ARE FROM WHICH THEY ARE COMPOSED!!!!!COMPOSED!!!!!
NaClNaCl
Flow chart – Pg. 50Flow chart – Pg. 50
Elements Elements represented by represented by symbolssymbols
Compounds Compounds represented by represented by formulasformulas
Pg. 52 Table 2.2Pg. 52 Table 2.2
Chemical ChangeChemical Change
A change that produces matter with A change that produces matter with a a different composition different composition than the than the original matteroriginal matter
Properties of MatterWhen a substance changes its composition, it undergoes a chemical change:
When pure hydrogen and pure oxygen react completely, they form pure water.
Is iron transforming into rust a Is iron transforming into rust a physical or chemical changephysical or chemical change
A.A. PhysicalPhysical
B.B. ChemicalChemical
Does the substance change composition or just change appearance?
The color of sulfur is The color of sulfur is yellow..yellow..
A.A. Physical Physical
B.B. ChemicalChemical
Does the substance change composition or just change appearance?
Dynamite explodes to form a Dynamite explodes to form a mixture of gasesmixture of gases
A.A. PhysicalPhysical
B.B. ChemicalChemical
Does the substance change composition or just change appearance?
Aluminum melts at 933 K Aluminum melts at 933 K
A.A. PhysicalPhysical
B.B. ChemicalChemical
Does the substance change composition or just change appearance?
Plants use COPlants use CO2 2 to make sugar to make sugar
A.A. PhysicalPhysical
B.B. ChemicalChemical
Does the substance change composition or just change appearance?
Chemical Reactions
One or more substances change into new substances
REACTANT(S) PRODUCT(S)
means “change into”, “produce”, “yields”
Chemical Property• The ability of a substance to
undergo chemical reactions and to form new substances
• Rusting, burning, fermenting, exploding, rotting, decomposing
• Iron and sulfur example
Indications that a chemical reaction has occurred
•Energy released or absorbed•Color change•Odor released•Production of a gas• Irreversibility•Production of light
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