Matter Rev

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Chapter 1: Sections 1.1 and Chapter 2: Sections 2.1, 2.2 & 2 .9
Classification of Matter Review: (Mostly on your own)
Physical States of Matter
 Solid
 Definite volume and shape.
 Crystalline
 Internal geometric structure is regular and repeating.
 Salt, sugar, quartz.
 Amorphous
 Internal structure has no regular pattern.
 Plastic, glass.
 Liquid
 Definite volume but indefinite shape.
 Gas
 Indefinite volume and indefinite shape.
Movement of Particles
 As you heat a substance, its particle move faster.
 Particles in the gas phase are moving the fastest.
 Liquid phase particles move with less energy than the gas phase.
 Solid phase particles are the slowest but they also have movement. (vibrations).
Substance
 A particular type of matter with a definite, fixed composition.
 Material that contains only one substance is either an element or a compound.
 Material that contains more than one substance is a mixture.
 More on mixtures later.
Elements
 Elements are the most basic form of matter.
 Cannot be broken into simpler substances by chemical or physical processes.
 A sample of an element contains only one type of atom.
 There are over 100 known elements.
 oxygen, carbon, iron, gold, helium, neon, sodium..
 Symbols: O, C, Fe, Au, He, Ne, Na...
 Some elements come as a couple!
 We call them “diatomics”: H2, N2, O2, F2, Cl2, Br2, I2
Know these.
 The elements are listed on the Periodic Table.
The Periodic Table
 Elements are arranged in the periodic table according to their properties.
 Each element has an “Atomic Number”.
 Metals are on the left, non-metals are on the right, metalloids between.
Compounds
 Pure substance composed of 2 or more elements.
 More than one type of atom chemically bonded together.
 Elemental composition always the same.
 Law of Constant Composition
 Molecules
 Water H2O 2 H atoms, 1 O atom
 Carbon dioxide CO2
Sugar, sucrose C12H22O11
 Salts (ionic compounds)
 Table salt, sodium chloride NaCl
 Calcium nitrate: Ca(NO3)2
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Types of Matter: Mixtures
 Most things are composed of more than one type of substance.
 We call these mixtures.
 In a mixture, each substance retains it chemical and physical properties.
 Examples of mixtures:
 A glass of tap water.
 A cake.
 Laundry detergent.
 Wood.
 Hair.
 Air.
More on Mixtures
 Mixtures may be difficult to study because they are composed of more than one
substance.
 They may not have “constant composition”
 A sample of tap water from my house may contain substances that a sample from
your house does not.
 However, in a mixture, each substance retains its own identity so we may be able to
separate the components.
Heterogeneous and Homogeneous Mixtures
 Heterogeneous
 Distinct regions with definite boundaries.
 May have multiple phases
 Wood, orange juice
 Homogeneous
 Solution
 No distinct regions, everywhere the same.
 Same phase
 Salt water, air
Compounds and Mixtures are Different
 In a mixture the substances are not bonded together and they retain their individual
characteristics.
 In a compound, the elements no longer retain their individual properties.
 To separate the elements in a compound you must use a chemical reaction of some
type.
 Mixtures can be separated by physical means.
 Evaporation, filtration, etc.
Physical and Chemical Properties
 A substance’s physical properties describe how it looks, feels, tastes, how heavy it is,
etc.
 A substance’s chemical properties describe how it reacts with other substances in
chemical reactions.
Physical Properties of Water
 Transparent
 Colorless
 Boiling Point 100°C (212°F)
 Freezing Point 0°C (32°F)
 Density 1.0 g/mL
Physical Changes
 When a substance undergoes a change without changing its chemical nature, this
event is called a physical change.
 Phase changes:
 Melting, freezing, boiling, etc.
 Change of form:
 Crushing salt into a powder.
 Pounding metal into a sheet.
Some Chemical Properties
 Propane gas is flammable.
 Iron has the tendency rust.
 Protein can be digested by enzymes in the stomach.
Chemical Changes (Processes)
 When a chemical reaction happens, chemical change occurs.
 When iron rusts, iron atoms react with oxygen to form iron oxide.
 When propane burns, it reacts with oxygen to form carbon dioxide and water.
Properties
 Intensive
 Does not depend on the amount of substance studied.
Density, boiling point, etc.
 Can be used to help identify a substance.
Extensive
 Depends on the amount of substance present.
 Pressure, mass, etc.
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Homework
 You should know (memorize) the names and symbols of the following elements :
 Elements #1-20 (don’t memorize their numbers!).
 Cr, Mn, Co, Ni, Fe, Cu, Zn, As, Br, Ag, Sn, I, Ba, Au, Hg, Pb, U.
 Ch 1 starts on p. 35
 #2 – 7, 21
 Ch 2 starts on p. 35
 #1 – 10, 20 – 25, 116 – 120
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