STATES OF MATTER Four States Solid Liquid Gas Plasma.

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STATES OF MATTER

Four StatesSolidLiquidGasPlasma

Based upon particle arrangement Based upon energy of particles Based upon distance between

particles

STATES OF MATTER

Kinetic Theory of Matter

Matter is made up of particles which are in continual random motion.

KINETIC THEORY

Kinetic Theory states that the tiny particles in all forms of matter are in constant motion.– Kinetic refers to motion

– Helps you understand the behavior of solid, liquid, and gas atoms/molecules as well as the physical properties

– Provides a model behavior based off three principals

KINETIC THEORY

3 Principles of Kinetic Theory– All matter is made of tiny particles

– These particles are in constant motion

– When particles collide with each other or the container, the collisions are perfectly elastic (no energy is lost)

STATES OF MATTER

4 States of Matter– Solid– Liquid– Gas– Plasma

STATES OF MATTERSOLIDS

Particles of solids are tightly packed, vibrating about a fixed position.

Solids have a definite shape and a definite volume. Heat

SOLIDS

Particles are tightly packed and close together

Particles do move but not very much Definite shape and definite volume

(because particles are packed closely and do not move)

Most solids are crystals Crystals are made of unit cells (repeating

patterns)– The shape of a crystal reflects the

arrangement of the particles within the solid

SOLIDS

Unit cells put together make a crystal lattice (skeleton for the crystal)

Unit cell crystal lattice solid

SOLIDSAmorphous Solid:

– A solid with no defined shape (not a crystal)

– A solid that lacks an ordered internal structure

– Examples: Clay, PlayDoh, Rubber, Glass, Plastic, Asphalt

SOLIDSAllotropes:

– Solids (elements or compounds) that appear in more than one form

– 2 or more different molecular forms of the same element in the same physical state (have different properties)

– Example: Carbon Powder = Graphite Pencil “lead” = graphite Hard solid = diamond

SOLIDS

SOLIDS Allotropes of Carbon:

a) diamond

b) graphite

c) lonsdaleite

d) buckminsterfullerene (buckyball)

e) C540

f) C70

g) amorphous carbon

h) single-walled (buckytube)

STATES OF MATTERLIQUIDParticles of liquids are

tightly packed, but are far enough apart to slide over one another.

Liquids have an indefinite shape and a definite volume.

Heat

LIQUIDS

Particles are spread apart Particles move slowly through a container No definite shape but do have a definite

volume Flow from one container to another Viscosity – resistance of a liquid to flowing

– Honey – high viscosity– Water – low viscosity

STATES OF MATTERGASParticles of gases are

very far apart and move freely.

Gases have an indefinite shape and an indefinite volume.

Heat

GASES

Particles are very far apart Particles move very fast No definite shape and No definite

volume

PHASE CHANGESDescription of Phase Change

Term for Phase Change

Heat Movement DuringPhase Change

Solid to liquid

MeltingHeat goes into the solid as it melts.

Liquid to solid

FreezingHeat leaves the liquid as it freezes.

A Phase is another way of saying a State (of Matter)

PHASE CHANGESDescription of Phase Change

Term for Phase Change

Heat Movement During Phase Change

Liquid to gas

Vaporization, which includes boiling and evaporation

Heat goes into the liquid as it vaporizes.

Gas to liquid

CondensationHeat leaves the gas as it condenses.

Solid to gas SublimationHeat goes into the solid as it sublimates.

But what happens if you raise the temperature to super-high levels…between 1000°C and 1,000,000,000°C ?

Will everything just be a gas?

STATES OF MATTERPLASMAA plasma is an

ionized gas.A plasma is a very

good conductor of electricity and is affected by magnetic fields.

Plasmas, like gases have an indefinite shape and an indefinite volume.

Plasma is the common state of matter

Ions = charged particles

STATES OF MATTER

SOLID LIQUID GAS PLASMA

Tightly packed, in a regular

patternVibrate, but do not move from place to place

Close together with no regular arrangement.Vibrate, move

about, and slide past each other

Well separated with no regular arrangement.Vibrate and

move freely at high speeds

Has no definite volume or shape

and is composed of electrical charged

particles

PLASMA Particles are extremely far apart Particles move extremely fast Only exists above 3000 degrees

Celsius Basically, plasma is a hot gas When particles collide, they break

apart into protons, neutrons, and electrons

Occurs naturally on the sun and stars

Some places where plasmas are found…

Flames

Lightning

Aurora (Northern Lights)

The Sun is an example of a star in its plasma state

A graph showing the heating curve for a substance.

A phase diagram showing the relationships of the states for a substance at different temperatures and pressures.

Any characteristic of a material that can be observed or measured without changing the identity of the material is a physical property.

In a physical change, the physical properties of a substance change, but the identity of the substance does not change.

A chemical property is any characteristic that gives a substance the ability to undergo a change that results in a new substance.

A chemical change is a change in the identity of a substance due to the chemical properties of that substance.

Pure SubstancesPure substances contain only one sort of particle. Many substances that in everyday language we call pure are really mixtures.

A pure substance can only be an element or a compound.

For example, a bottle of pure mineral water has, according to the label, the following contents :

•Calcium•Magnesium•Sodium•Potassium•Bicarbonate•Chloride•Sulphate•Fluoride!

If it was really pure water, in the scientific meaning of the word, it would contain only water particles, H20.

Elements, Molecules and Compounds

Some elements, such as the noble gases, exist as individual atoms.

Often, elements consist of two or more atoms joined together. We call these molecules.

If more than one type of atom is in a molecule, we call it a compound.

By asking these questions scientists can classify matter into:

Mixtures – two or more substances that are not chemically combined with each other and can be separated by physical means. The substances in a mixture retain their individual properties.– Solutions – a special kind of mixture where one

substance dissolves in another.

Elements – simplest form of pure substance. They cannot be broken into anything else by physical or chemical means.

Compounds – pure substances that are the unions of two or more elements. They can be broken into simpler substances by chemical means.

Is it uniform throughout?

If the answer is no, the matter is a heterogeneous mixture.– Considered the “least mixed.”– Does not appear to be the same

throughout.– Particles are large enough to be

seen and to be separated from the mixture.

Examples of heterogeneous mixtures

Sand and pebbles Oil and water Powdered iron and powdered

sulfur

Granite is a heterogeneous mixture.

Matter

Heterogeneous mixture

Is it uniform throughout

Homogeneous mixture

Pure substance

Solution

Can it be separated by

physical means

Mixture

Colloid

Can it be decomposed into other substances by chemical processes

Element Compound

SolventSolute

contains

Dissolved down to atomic or molecular

level

yesno

yesno

yes no

no yes

Is it uniform throughout?If the answer is yes, the matter is a

homogeneous mixture (looks the same throughout).

A mixture that appears to be the same throughout.

It is “well mixed.”

The particles that make up the mixture are very small and not easily recognizable.

Colloids

Particles are mixed together but not dissolved.

The particles are relatively large and are kept permanently suspended.

However, the particles are larger than individual atoms or molecules.

0

20

40

60

80

100

1st

Qtr

2nd

Qtr

3rd

Qtr

4th

Qtr

East

West

North

Colloids

A colloid will not separate upon standing.

The particles are constantly colliding, and this allows a colloid to scatter light – thus colloids often seem cloudy.

Solutions If the particles in a homogeneous mixture are

at an atomic or molecular level (breaks down to individual atoms or molecules) – it is a solution.

A solution is a type of homogeneous mixture formed when one substance dissolves in another.

It is the best mixed of all mixtures. A solution always has a substance that is

dissolved and a substance that does the dissolving.

The substance that is dissolved is the solute and the substance that does the dissolving is the solvent.

Ocean water is a solution

The universal solvent: Water

Water as a solvent

Many liquid solutions contain water as the solvent.

Ocean water is basically a water solution that contains many salts.

Body fluids are also water solutions.

Types of solutions

Gas Gas Air (oxygen in nitrogen)

Gas Liquid Soda water (carbon dioxide in water)

Solid Liquid Ocean water (salt in water)

Solute Solvent Example

Solid Solid Gold jewelry (copper in gold)

Metals dissolved in metals are called

alloys.

Air is a solution of oxygen and other gases dissolved in nitrogen

Alloys

Brass is an alloy of copperand zinc.

Stainless steel is a mixtureof iron and chromium.

Can it be separated by physical means?

If the answer is no, the matter is a pure substance.– An element– Or a compound

Elements Elements are the simplest pure substance.

– An element can not be changed into a simpler substance by heating or any chemical process.

The smallest particle of an element that has the properties of that element is called an atom.– An atom is the basic building block of matter.

There are more than one hundred known elements in the universe listed on the periodic table of elements.– These elements combine in such a way to

create millions of compounds.

Elements

All elements are made of atoms.

Atoms of the same element are alike.

Atoms of different elements are different.

Elements

In 1813, a system of representing elements with symbols was introduced.

– Each symbol consists of one or two letters.

– Two letters are needed for a chemical symbol when the first letter of that element’s name has already been used.

Common Elements

Aluminum Al

Bromine Br

Calcium Ca

Carbon C

Gold Au

Helium He

Hydrogen H

Nitrogen N

Compounds

Compounds are also pure substances.

But compounds are made from more than one element.

Water is a compound. Water can be broken

down into simpler substances – hydrogen and oxygen.

Chemical Reactions

Chemical reactions, or chemical changes, happen when the atoms in one or more chemicals split up and join together in new ways.

For example, hydrogen can react with oxygen :

hydrogen + oxygen → water

Chemical Reactions

hydrogen + oxygen → water

Before the reaction the oxygen atoms go round in pairs, and the hydrogen atoms go round in pairs. When they react we get two new molecules, of the compound water.

Each of these molecules has three atoms, two hydrogen atoms joined to one oxygen atom.We can write this as H2O.

Types of Reaction

There are several different groups that we can put reactions into. These include :

combustiondisplacementneutralizationoxidationprecipitationthermal decomposition

The reaction of sugar with concentrated sulphuric acid.

Types of Reaction

When a reaction takes place, things happen. There may be a gas given off, a colour change or a solid material appearing. There could also be changes we can’t see, such as a temperature change.

One important thing to remember about chemical reactions is that the mass of the reactants (the chemicals we start with) is always the same as the mass of the products (the chemicals we end with).

This is the Law of Conservation of Matter

Combustion

This is the name we give to reactions when things burn in air. Combustion is a special sort of oxidation reaction. It happens quickly and a flame is produced which heats the surroundings.

As we have already seen, hydrogen will react with oxygen – it burns to form water.

Most fuels burn in air to form water and carbon dioxide :

methane + oxygen carbon dioxide + water

Oxidation

In oxidation reactions, oxygen combines with a substance to make an oxide.

For example iron will go rusty :

iron + oxygen iron oxide

Adding pure oxygen makes reactions go faster than they would in air. Here is a picture of a biscuit burning!

Thermal Decomposition

In this type of reaction, a substance breaks down into simpler parts when it is heated.

For example, copper carbonate will decompose when heated :

copper carbonateheat

copper oxide + carbon dioxide

If we measure the mass of copper carbonate before the reaction, and then the mass of copper oxide left after the reaction, the mass of the copper oxide will be lower.The mass has not disappeared. The missing mass is that of the carbon dioxide gas which has escaped into the air.

Displacement

In a displacement reaction, one metal ‘kicks out’ a less reactive one.

For example, when iron filings are added to copper sulphate solution, copper metal starts to appear.

iron + copper sulphate copper + iron sulphate

Displacement

iron + copper sulphate copper + iron sulphate

The iron wants to be with the sulphate more than the copper does. We say that iron is more reactive than copper.

When the iron atoms are mixed with the copper sulphate atoms, the iron atoms ‘kick out’ the copper atoms and join on to the sulphate ions (particles).

We see the red / brown copper metal start to appear in place of the grey iron, and the solution changes colour from blue to green, as copper sulphate is blue but iron sulphate is green.

Displacement

If an insoluble product is formed in a reaction, it suddenly appears. We say it precipitates, and the solid is called the precipitate.

This reaction happens if we blow into lime water (calcium oxide solution). The carbon dioxide from our breath joins up with the calcium oxide to form calcium carbonate, which is a white, insoluble material.

neutralization

Neutralization (or acid/base) occurs when an acid combines with a base to produce a salt and water

HCl (aq) + NaOH (aq) → NaCl + H2O

Precipitation

If an insoluble product (a solid in the liquid solution) is formed in a reaction, it suddenly appears. We say it precipitates, and the solid is called the precipitate.

This reaction happens if we blow into lime water (calcium oxide solution). The carbon dioxide from our breath joins up with the calcium oxide to form calcium carbonate, which is a white, insoluble material.

calcium oxide + carbon dioxide calcium carbonate