MATTER

PURE SUBSTANCE

ELEMENT COMPOUND

Carbon (C) H2O

MIXTURE

?

NOW LETS DISCOVER MATTER AS MIXTURES

THUS FAR WE HAVE REVIEWED MATTER AS PURE SUBSTANCES.

Classification

MatterHas mass and takes up space

MixtureVariable Composition

SubstanceDefine composition

CompoundTwo or more

kinds of atoms

ElementOne kind of

atom

HeterogeneousUnevenly mixed

HomogeneousEvenly mixed

Solution ProcessA mixture is formed by two or moreelements or compounds that are physicallymixed together but not chemically joined.example: salt and pepperMixture can be:

HomogeneousEvenly mixed

HeterogeneousUnevenly mixed

The two types of Mixtures :

Classifying mixtures

2) HETEROGENEOUS1) HOMOGENEOUS

HomogeneousEvenly mixed

HeterogeneousUnevenly mixed

Mixture is formed by two or more elements or compounds that are physically mixed together but not chemically joined.

example: salt and pepper

The Two Types of Mixture1. Solution is a homogeneous mixture in which

one substances is dissolved in another

substance. It consists of a solute and solvent.

Solvent is the substance in which the solute is dissolved

Solute is the substance dissolved in the solution.

When sugar, a solute and water asolvent are mixed, a water sugar solution is formed.

2. Suspension is a mixture of water with non-dissolve material

Example sand and water

The Two Types of Mixture (Cont.)

• Solute is the substance dissolved in the solution– Particles may be

ions, atoms, or molecules

• Solvent is the substance in which the solute is dissolved

MixturesSummary

Heterogeneous Mixture (Suspension)

Homogeneous Mixture (Solution)

Not evenly mixed Evenly mixed

Individual components retain their own properties

Properties of combined components are usually different than those of each component

Individual components can be easily seen

Individual components can not be easily seen

Can be easily separated Not as easily separated

Ex.: salt & pepper mix, rocks, cereal, bag of assorted candy

Ex. salt-water solution, tea, kool-Aid drink

SolubilitySolubility is the amount of a substance that can dissolve in 100 grams of solvent at a given time.

• The ability of a solvent to dissolve a solute depends on temperature and molecular structure.

• Like dissolve like:

• When the temperature of a liquid increases, The solubility of the solvent increases.

SOLUBILITY GRAPH

Classifying Matter

Matter

Pure Substances Mixtures

Elements Compounds

Homogeneous Heterogeneous

He, O H2O, NaCl

Tea, kool-aid Rocky Road ice cream, muddy water

Review: How matter is classified

1. Tossed salad2. Salt water3. Kool-aid4. Muddy water5. OJ with pulp

Practice ProblemsPractice Problems

1. He 2. Ho 3. Ho 4. He 5. He 6. Ho 7. He 8. He 9. He 10. Ho

6. Tea7. Banana nut

bread8. Pizza9. Blood10. Brass

Determine whether each is a heterogeneous or homogeneous mixture:

Answers:

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Classify the following substances as:Pure substance, heterogeneous mixture, or homogeneous mixture

Gatorade Homogenous mixture

Fruit Loops Heterogeneous mixture

Pure substanceGasoline

Dirt Heterogeneous mixture

Sugar Crystals Pure Substance

Air Homogeneous mixture

Granite Heterogeneous mixture

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More review

1) We are studying CHEMISTRY, the study of ________and how it ________.

2) Matter is anything that has___ and takes up ___.

3) ___ are the basic building blocks of matter.

4) Matter can be classified as either a ___ or a ___.

5) Substances are either ___ or ___.

1. matter, changes 2. mass, space 3. atoms 4. pure substance, mixture 5. elements, compounds

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Answers:

MATTER AS MIXTURESMATTER AS MIXTURES Mixtures are combinations of 2 or more substances

where each substance retains its individual properties.

HOW ARE MIXTURES DIFFERENT FROM COMPOUNDS?

HOW ARE MIXTURES LIKE COMPOUNDS? THEY ARE MADE FROM TWO OR MORE SUBSTANCES

MIXTURES DO NOT FORM CHEMICAL BONDS.

…a mixture that is the same throughout. A homogeneous mixture has a

composition and properties that are identical regardless of the sample

one phase

uniformly mixed

won’t settle out

small particles

Ways to identify a homogeneous mixture:

A SOLUTION is another name for a homogeneous mixture

is

… a mixture that is visibly differentthroughout. Heterogenous mixtures have a composition and properties that differ

in any given sample.

not uniformly mixed

more than one phase

will settle out

larger particles

is

Ways to identify a homogeneous mixture:

HETEROGENEOUS MIXTURESThere are special types of heterogeneous mixtures:• Suspensions-appear uniform when mixed but settle out.

– Chocolate Quik

– Muddy water

– Pulpy oj

– Oil & Vinegar dressing

• Colloids-appear uniform but they do not settle out. However, their particles are too large to be classified as a homogeneous solution.– Gelatin

– Milk

– Smoke

– Fog

– mayonnaise

• Pure Substances– Made of either elements or

compounds that are chemically bonded.

– Cannot be separated by physical means.

– When combined they take on new properties different from the original elements.

– Examples:• Glucose: C6H12O6

• Table Salt: NaCl• Oxygen Gas: O2

• Carbon Dioxide CO2

• Mixtures:– Two or more substances mixed

together but not chemically combined.

• Tea = Crushed Leaf + H2O• Rocks = minerals + sediments +

organic matter• Sugar Water = Sugar + H2O

– Each component retains its own identity; it does not change into something else.

– Can be separated by physical means

– Examples:• Sweet tea• Trail mix• Air (O2, N2, CO2, Ar)

Now, lets put it all together and determine how to tell substances (compounds and elements)

from mixtures.

Elements, Compounds, and Mixtures

hydrogenatoms

oxygen atomshydrogenatoms

Two of the descriptions to the right apply to each bottle below. Determine the appropriate descriptions..

a. Two types of atoms evenly mixed

b. Two types of atoms chemically combined

c. One type of atom

d. Two types of atoms mixed

e. An element

f. A solution

g. A compound

h. A mixture2_______1_______ 3_______ 4_______d & h b & g c & e a & f

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