MATTER: MIXTURES AND ELEMENTS AND COMPOUNDS You will distinguish between physical and chemical...
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Transcript of MATTER: MIXTURES AND ELEMENTS AND COMPOUNDS You will distinguish between physical and chemical...
You will distinguish between physical and chemical propertiesYou will classify matter by composition.You will explain the fundamental law of the conservation of
mass
WHAT YOU’LL LEARN
A mixture is a combination of two or more substances in which each pure substance retains its individual chemical properties
This is a physical blending, not a chemical blending.
Composition of the mixture can vary Can be physically separated
MIXTURES
Heterogeneous Mixture- one that does not blend smoothly throughout and which the individual substances remain distinct
Examples: Sand and Water, Oil and Water, Cement
Homogeneous Mixture (Solutions)- has constant composition throughout; it always has a single phase
Examples: salt water, vinegar, alloys
HETEROGENEOUS VS. HOMOGENOUS
A technique that results in the formation of pure solid particles of a substance from a solution containing the dissolved substance
CRYSTALLIZATION
A technique that separates the components of a mixture on the basis of the tendency of each to travel or be drawn across the surface of another material
CHROMATOGRAPHY
Elements- are the simplest form of matter that can exist under NORMAL laboratory conditions Cannot be separated into simpler substances by chemical means
Are the building blocks for all other --substances
Compounds-are substances that can be separated into simpler substances by chemical means
ELEMENTS AND COMPOUNDS
Elements comprising compounds combine in definite proportions
Regardless of the amount, a compound is always composed of the same elements in the same proportion by mass
LAW OF DEFINITE PROPORTIONS
Water Methane
Percent by Mass- the ratio of the mass of each element to the total mass of the compound as a percentage
PERCENT BY MASS
x100compound of mass
element of mass(%) massby percent
A 78.0g sample of an unknown compound contains 12.4 g of hydrogen. What is the percent by mass of hydrogen in the compound?
PRACTICE PROBLEM
100x78.0g
12.4gmassby Percent
15.9% Hydrogen
MORE PRACTICE
Material Pure Substance or Mixture
Element, Compound, Homogeneous, Heterogeneous
Limestone (CaCO3)
Air
Bronze
Copper
Sugar + water
Concrete
Pure Water
Caffeine
Material Pure Substance or Mixture
Element, Compound, Homogeneous, Heterogeneous
Limestone (CaCO3) PURE SUBSTANCE COMPOUND
Air MIXTURE HOMOGENEOUS
Bronze MIXTURE HOMOGENEOUS
Copper PURE SUBSTANCE ELEMENT
Sugar + water MIXTURE HOMOGENEOUS
Concrete MIXTURE HETEROGENEOUS
Pure Water PURE SUBSTANCE COMPOUND
Caffeine PURE SUBSTANCE COMPOUND
MORE PRACTICE!
SUMMARY
MATTER
MatterMatter
SubstanceDefinite composition
(homogeneous)
SubstanceDefinite composition
(homogeneous)
Element(Examples: iron, sulfur,
carbon, hydrogen,oxygen, silver)
Element(Examples: iron, sulfur,
carbon, hydrogen,oxygen, silver)
Mixture ofSubstances
Variable composition
Mixture ofSubstances
Variable composition
Compound(Examples: water.
iron sulfide, methane,aluminum, silicate)
Compound(Examples: water.
iron sulfide, methane,aluminum, silicate)
Homogeneous mixtureUniform throughout,also called a solution
(Examples: air, tap water,gold alloy)
Homogeneous mixtureUniform throughout,also called a solution
(Examples: air, tap water,gold alloy)
Heterogeneous mixtureNonuniform
distinct phases(Examples: soup, concrete, granite)
Heterogeneous mixtureNonuniform
distinct phases(Examples: soup, concrete, granite)
Chemicallyseparable
Physicallyseparable
Read Oobleck Lab-There will be a QUIZ before the lab over what you will be doing!
Make sure you bring the lab back-you will not receive another one. =)
Book work: PAGE 69: 15-17 PAGE 76: 21-23 PAGE 77: 25-27, 30
HOMEWORK =)