lec1 matter
TRANSCRIPT
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Matter
Matter
Takes up Space
Can be Touched
Has Mass
Matter
Properties
Physical
Physical properties can be measure without changing the basic identity of the substance
Chemical
Chemical properties describe how substances react or change to form different substances
Physical Properties
State or Phase Melting and freezing point Texture Color Shiny/dull Hardness Flexibility Ductile
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Physical Properties of Elements
Some physical properties ofcopper are:
Color Red-orange
Luster Very shinyMelting point 1083°CBoiling point 2567°CConduction of electricity ExcellentConduction of heat Excellent
Chemical Properties
Now matter starts changing it’s composition
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A pure substance is classified as Matter with a specific composition.
An element when composed of one type of atom.
A compound when composed of two or more elements combined in a definite ratio.
Pure Substances
Elements• If a pure substance cannot be decomposed into
something else, then the substance is an element.• There are 114 elements known.• Each element is given a unique chemical symbol
(one or two letters).• Elements are building blocks of matter.• The earth’s crust consists of 5 main elements.• The human body consists mostly of 3 main
elements.
Classification of Matter
Elements
Classification of Matter
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A symbol Represents the name of an element. Consists of 1 or 2 letters. Starts with a capital letter.
Examples:1-Letter Symbols 2-Letter SymbolsC carbon Co cobaltN nitrogen Ca calciumF fluorine Al aluminum
O oxygen Mg
magnesium
Symbols of Elements
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Some symbols are derived from Latin names as shownbelow:
Cu, copper (cuprum) Au, gold (aurum)
Fe, iron (ferrum) Ag, silver (argentum)
Symbols from Latin Names
Compounds• Most elements interact to form compounds.
• Example, H2O
• The proportions of elements in compounds are the same irrespective of how the compound was formed.
• Law of Constant Composition (or Law of Definite Proportions):–The composition of a pure compound is always
the same.
Classification of Matter
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Compounds
Compounds Contain two or more elements
in a definite ratio.
Salt (NaCl)
Table sugar (C12H22O11)
Water (H2O)
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Elements in a Compound
“Table salt” is a compound that contains the elements sodium and chlorine.
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Mixtures
A mixture is matter that consists of Two or more substances that are physically mixed,
not chemically combined. Two or more substances in different proportions. Substances that can be separated by physical
methods.
Mixtures• Heterogeneous mixtures are not uniform
throughout.• Homogeneous mixtures are uniform throughout.• Homogeneous mixtures are called solutions.
Classification of Matter
Separation of Mixtures
Separation of Mixtures• Mixtures can be separated if their physical
properties are different.• Solids can be separated from liquids by means of filtration.
• The solid is collected in filter paper, and the solution, called the filtrate, passes through the filter paper and is collected in a flask.
Properties of Matter
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Identify each of the following as a pure substance or a mixture.
A. pasta and tomato sauce
B. aluminum foil
C. helium
D. air
Learning Check
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Identify each of the following as a pure substance or a mixture.
A. pasta and tomato saucemixture
B. aluminum foil pure substance
C. helium pure substance
D. air mixture
Solution
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Identify each of the following as a homogeneous orheterogeneous mixture:
A. hot fudge sundae
B. shampoo
C. sugar water
D. peach pie
Learning Check
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Identify each of the following as a homogeneous orheterogeneous mixture:
A. hot fudge sundae heterogeneous mixture
B. shampoo homogeneous mixture
C. sugar water homogeneous mixture
D. peach pie heterogeneous mixture
Solution