Matter and Change Mrs. Harvey - Chemistry - GHS - 2010.

Matter and Change

Mrs. Harvey - Chemistry - GHS - 2010

What is Matter?

Matter- anything that has mass and takes up space.

Mass- measure of the amount of matter

NOT Weight – it is due to gravity, and changes from location to location; mass is always constant.


Properties

Physical Properties- a property that can be observed and measured without changing the composition.

Examples- color, hardness, m.p., b.p.

Chemical Properties- a property that can only be observed by changing the composition of the material.


Physical ChangeA change in a substance that does not involve a change in the identity of the substance.

Example:

Phase Changes


Phase Differences

Solid – definite volume and shape; particles packed in fixed positions.Liquid – definite volume but indefinite shape; particles close together but not in fixed positionsGas – neither definite volume nor definite shape; particles are at great distances from one anotherPlasma – high temperature, ionized phase of matter as found on the sun.


Three Phases


Copper Phases - Solid


Copper Phases - Liquid


Copper Phases – Vapor (gas)


States of Matter

Solid

Liquid

Gas

Definite Volume?

YES

YES

NO

Definite Shape?

YES

NO

NO

Temp. increase

Small Expans.

Small Expans.

Large Expans.

Com-pressible?

NO

NO

YES


Solid Liquid Gas

Melt Evaporate

CondenseFreeze

SUBLIMATION


Chemical ChangeA change in which one or more substances are converted into different substances.

Heat and light are often evidence of a chemical change.


Types of Matter

Substance- pure matter that is uniform (all the same) and has a definite composition (examples are elements & compounds)

Mixture- more than one kind of matter; has a variable composition


Classification of Matter


MixturesPhysical blend of at least two

substances; variable compositionHeterogeneous- mixture is not

uniform in compositionChocolate chip cookie, gravel, soil.Homogeneous- same composition

throughout; called “solutions”Kool-aid, air, salt waterEvery part keeps it’s own properties.


Separation of a Heterogeneous Mixture

The constituents of the mixture retain their identity and may be separated by physical means.


Solutions

Homogeneous mixtureMixed molecule by moleculeCan occur between any state of

mattergas in gas; liquid in gas; gas in liquid;

solid in liquid; solid in solid (alloys), etc.


Solutions

Like all mixtures, they keep the properties of the components.

Some can be separated easily by physical means: rocks and marbles, iron filings and sulfur

Other methods: distillation- takes advantage of different boiling points


Separation of a Homogeneous Mixture

Distillation


Classification of Matter


The smallest unit of an element that maintainsthe properties of that elementElement

A pure substance made of only one kind of atom

Atom


A substance that is made from the atoms of two or more elements that are chemically bonded.

Sucrose – C12H22O11

Sucrose is also known as table sugar, and is used to make Gummy Bears!

Compound


Separation of a CompoundThe Electrolysis of water

Water Hydrogen + Oxygen

H2O H2 + O2

Reactant Products

Compounds must be separated by chemical means.

With the application of electricity, water can be separated into its elements


Compound or Mixture

Compound Mixture

Made of one kindof material

Made of more thanone kind of material

Made by a chemical change

Made by a physical change

Definitecomposition

Variablecomposition


Matter and Change Mrs. Harvey - Chemistry - GHS - 2010.

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