matter properties & changes matter – anything that has mass and takes up space substance -...

MatterMatterProperties & ChangesProperties & Changes

MatterMatter – anything that has mass and takes – anything that has mass and takes up spaceup space

SubstanceSubstance - matter that has a uniform and - matter that has a uniform and unchanging composition…also known as a unchanging composition…also known as a pure substancepure substance

Properties of MatterProperties of MatterSubstancesSubstances

Pure substance or a mixture? Topic 1Topic 1

Chemistry and Matter: Basic ConceptsChemistry and Matter: Basic Concepts Chemistry and Matter: Basic ConceptsChemistry and Matter: Basic Concepts

• A substance is matter, either an element or compound, with the same fixed composition and properties.

• A sample of matter is either pure—made up ofonly one kind of matter— or it is a mixture of different kinds of matter.

• A mixture is a combination of two or more substances in which the basic identity of eachsubstance is not changed.

• Unlike pure substances, mixtures do not have specific compositions.

Topic 1Topic 1


Pure substance or a mixture?

Comparison of a Compound and a Comparison of a Compound and a MixtureMixture

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• A physical change is a change in matter that does not involve a change in the chemical identity of individual substances.

• Examples of physical changes include:

• boiling,

• freezing,

• melting,

• evaporating,

• dissolving,

• and crystallizing.

Topic 1Topic 1



• Physical properties are characteristics that a sample of matter exhibits without any change in its identity.

Topic 1Topic 1



Physical Properties of MatterPhysical Properties of Matter

A A physical propertyphysical property is a characteristic that is a characteristic that can be observed or can be observed or measured without measured without changing the changing the sample’s composition. sample’s composition.

Physical Properties Movie

Examples of Physical PropertiesExamples of Physical Properties

Melting pointMelting point Boiling pointBoiling point Freezing pointFreezing point ColorColor OdorOdor HardnessHardness TasteTaste

MalleabilityMalleability DuctilityDuctility MagnetismMagnetism Crystalline shapeCrystalline shape LusterLuster Refractive IndexRefractive Index

Physical properties can be further Physical properties can be further described as being one of two typesdescribed as being one of two types

Extensive propertiesExtensive properties are dependent are dependent upon the amount of substance presentupon the amount of substance present

For example, mass, which depends on For example, mass, which depends on the amount of substance there is, is an the amount of substance there is, is an extensive property.extensive property.

Length and volume are also extensive Length and volume are also extensive properties.properties.

Extensive and Intensive Extensive and Intensive Properties Properties

Intensive propertiesIntensive properties are independent of the are independent of the amount of substance presentamount of substance present

For example, density of a substance (at constant For example, density of a substance (at constant temperature and pressure) is the same no temperature and pressure) is the same no matter how much substance is present. matter how much substance is present.

Color is another example of an intensive Color is another example of an intensive propertyproperty

Melting point, boiling point & freezing points are Melting point, boiling point & freezing points are also intensive propertiesalso intensive properties

Extensive and Intensive Extensive and Intensive Properties Properties

Physical ChangesPhysical Changes

Changes which alter a substance without Changes which alter a substance without changing its composition, are known as changing its composition, are known as physical changesphysical changes..

An example is the crumpling of a sheet of An example is the crumpling of a sheet of aluminum foil.aluminum foil.

While the foil goes from a smooth, flat, mirror-While the foil goes from a smooth, flat, mirror-like sheet to a round, compact ball, the actual like sheet to a round, compact ball, the actual composition of the foil is unchanged—it is still composition of the foil is unchanged—it is still aluminumaluminum

Phase changes are Phase changes are another example of another example of physical changesphysical changes

When you encounter terms When you encounter terms such as boil, freeze, such as boil, freeze, condense, vaporize, or condense, vaporize, or melt in your study of melt in your study of chemistry, the meaning chemistry, the meaning generally refers to a phase generally refers to a phase change in matter.change in matter.

Physical ChangesPhysical Changes

Chemical Changes

chemical change, the change of one or more substances into other substances.

• A chemical property always relates to a

• Another term for chemical change is chemical reaction.

Topic 1Topic 1


The ability of a substance to combine with or The ability of a substance to combine with or change into one or more other substances is change into one or more other substances is called a called a chemical propertychemical property..

The ability of iron to form rust when combined The ability of iron to form rust when combined with air is an example of a chemical property of with air is an example of a chemical property of ironiron

Similarly, the inability of a substance to change Similarly, the inability of a substance to change into another substance is also a chemical into another substance is also a chemical property.property.

Chemical Properties of MatterChemical Properties of Matter

A process that involves one or more A process that involves one or more substances changing into new substances substances changing into new substances is called a is called a chemical changechemical change,, which is which is commonly referred to as a chemical commonly referred to as a chemical reaction.reaction.

The new substances formed in the The new substances formed in the reaction have different compositions and reaction have different compositions and different properties from the substances different properties from the substances present before the reaction occurred.present before the reaction occurred.

Chemical ChangesChemical Changes

Chemical Changes

• All matter is made of atoms, and any chemical change involves only a rearrangement of the atoms. Atoms do not just appear. Atoms do not just disappear.

• This is an example of the law of conservation of mass, which says that in a chemical change, matter is neither created nor destroyed. It would be equally correct to call this the law of conservation of matter.

Topic 1Topic 1


When a freshly exposed iron surface is left When a freshly exposed iron surface is left in contact with air, it slowly changes into a in contact with air, it slowly changes into a new substance, namely, the rust.new substance, namely, the rust.

The iron reacts with oxygen in the air to The iron reacts with oxygen in the air to form a new substance, rust. form a new substance, rust.


When you encounter terms such as When you encounter terms such as explode, rust, oxidize, corrode, tarnish, explode, rust, oxidize, corrode, tarnish, ferment, burn, rot, or dissolve in acid, the ferment, burn, rot, or dissolve in acid, the meaning generally refers to a chemical meaning generally refers to a chemical reaction in which reactant substances reaction in which reactant substances produce different product substances. produce different product substances.


Categories of MatterCategories of Matter

Mixtures & Compounds video clip

Elements, Compounds, & MixturesElements, Compounds, & Mixtures

An An elementelement is a pure substance that cannot be is a pure substance that cannot be separated into simpler substances by physical or separated into simpler substances by physical or chemical means.chemical means.

Each element has a unique chemical name and Each element has a unique chemical name and symbol. symbol.

The chemical symbol consists of one, two, or The chemical symbol consists of one, two, or three letters; the first letter is always capitalized three letters; the first letter is always capitalized and the remaining letter(s) are always and the remaining letter(s) are always lowercase.lowercase.

ElementsElements

Elements take up one Elements take up one block on the periodic block on the periodic tabletable

CompoundsCompounds

A A compoundcompound is a combination of two or is a combination of two or more different elements that are more different elements that are combined chemically.combined chemically.

Water, table salt, table sugar, and Water, table salt, table sugar, and aspirin are examples of common aspirin are examples of common compounds.compounds.

Unlike elements, compounds can be Unlike elements, compounds can be broken down into simpler substances by broken down into simpler substances by chemical means.chemical means.

CompoundsCompounds

The chemical symbols of the periodic table The chemical symbols of the periodic table make it easy to write the formulas for make it easy to write the formulas for chemical compounds. chemical compounds.

For example, table salt, or sodium chloride, is For example, table salt, or sodium chloride, is composed of one part sodium (Na) and one composed of one part sodium (Na) and one part chlorine (Cl), and its chemical formula is part chlorine (Cl), and its chemical formula is NaCl. NaCl.

Water is composed of two parts hydrogen (H) Water is composed of two parts hydrogen (H) to one part oxygen (O), and its formula is to one part oxygen (O), and its formula is HH22O. O.

A A mixturemixture is a combination of two or more is a combination of two or more pure substances in which each pure pure substances in which each pure substance retains its individual chemical substance retains its individual chemical properties.properties.

MixturesMixtures

Mixtures themselves are classified as Mixtures themselves are classified as either heterogeneous or homogeneous.either heterogeneous or homogeneous.

A A heterogeneous mixtureheterogeneous mixture is one that is one that does not blend smoothly throughout and in does not blend smoothly throughout and in which the individual substances remain which the individual substances remain distinct.distinct.

The sand and water mixture is an example The sand and water mixture is an example of a heterogeneous mixture. of a heterogeneous mixture.

Types of MixturesTypes of Mixtures

A A homogeneous mixturehomogeneous mixture has constant has constant composition throughout; it always has a composition throughout; it always has a single phase.single phase.

Homogeneous mixtures are also referred Homogeneous mixtures are also referred to as to as solutionssolutions..

An example of a homogeneous mixture An example of a homogeneous mixture would be salt water.would be salt water.


Comparison of a Solution and a MixtureComparison of a Solution and a Mixture





The solid–solid solution The solid–solid solution known as steel is called known as steel is called an alloy.an alloy.

An alloy is a An alloy is a homogeneoushomogeneous mixture mixture of metals, or a mixture of of metals, or a mixture of a metal and a nonmetal a metal and a nonmetal in which the metal in which the metal substance is the major substance is the major component.component.


Separating MixturesSeparating Mixtures

Because the substances in a mixture are Because the substances in a mixture are physically combined, the processes used physically combined, the processes used to separate a mixture are physical to separate a mixture are physical processes that are based on the difference processes that are based on the difference in physical properties of the substances.in physical properties of the substances.

FiltrationFiltration

Heterogeneous Heterogeneous mixtures composed of mixtures composed of solids and liquids are solids and liquids are easily separated by easily separated by filtration.filtration.

FiltrationFiltration is a is a technique that uses a technique that uses a porous barrier to porous barrier to separate a solid from a separate a solid from a liquid.liquid.

DistillationDistillation

Most homogeneous Most homogeneous mixtures can be mixtures can be separated by separated by distillation distillation

DistillationDistillation is a is a separation technique separation technique that is based on that is based on differences in the differences in the boiling points of the boiling points of the substances involved.substances involved.

CrystallizationCrystallization

CrystallizationCrystallization is a is a separation technique separation technique that results in the that results in the formation of pure solid formation of pure solid particles of a substance particles of a substance from a solution from a solution containing the containing the dissolved substance.dissolved substance.

ChromatographyChromatography

ChromatographyChromatography is a technique that separates is a technique that separates the components of a mixture (called the mobile the components of a mixture (called the mobile phase) on the basis of the tendency of each to phase) on the basis of the tendency of each to travel or be drawn across the surface of another travel or be drawn across the surface of another material (called the stationary phase).material (called the stationary phase).

The separation occurs because the various The separation occurs because the various components of the ink spread through the paper components of the ink spread through the paper ant different rates.ant different rates.

Paper ChromatographyPaper Chromatography

States of MatterStates of Matter

In fact, all matter that exists on Earth can be In fact, all matter that exists on Earth can be classified as one of these physical forms called classified as one of these physical forms called states of matterstates of matter. .

Scientists recognize a fourth state of matter Scientists recognize a fourth state of matter called plasma, but it does not occur naturally on called plasma, but it does not occur naturally on Earth except in the form of lightning bolts.Earth except in the form of lightning bolts.

The three main states of matter are: solid, liquid, The three main states of matter are: solid, liquid, & gas.& gas.

SolidsSolids

A A solidsolid is a form of matter is a form of matter that has its own definite that has its own definite shape and volume.shape and volume.

The particles of matter in a The particles of matter in a solid are very tightly solid are very tightly packed; when heated, a packed; when heated, a solid expands, but only solid expands, but only slightly.slightly.

Because its shape is Because its shape is definite, a solid may not definite, a solid may not conform to the shape of the conform to the shape of the container in which it is container in which it is placed.placed.

Solid StructureSolid Structure





LiquidsLiquids

A A liquidliquid is a form of is a form of matter that flows, has matter that flows, has constant volume, and constant volume, and takes the shape of its takes the shape of its container.container.

The particles in a liquid The particles in a liquid are not rigidly held in are not rigidly held in place and are less closely place and are less closely packed than are the packed than are the particles in a solid: liquid particles in a solid: liquid particles are able to move particles are able to move past each other. past each other.

LiquidsLiquids

This allows a liquid to flow This allows a liquid to flow and take the shape of its and take the shape of its container, although it may container, although it may not completely fill the not completely fill the container. container.

Because of the way the Because of the way the particles of a liquid are particles of a liquid are packed, liquids are packed, liquids are virtually incompressible. virtually incompressible. Like solids, liquids tend to Like solids, liquids tend to expand when heated.expand when heated.

Liquid StructureLiquid Structure





GasesGases

AA gasgas is a form of matter that flows to conform to is a form of matter that flows to conform to the shape of its container and fills the entire the shape of its container and fills the entire volume of its container.volume of its container.

Compared to solids and liquids, the particles of Compared to solids and liquids, the particles of gases are very far apart.gases are very far apart.

Because of the significant amount of space Because of the significant amount of space between particles, gases are easily compressed.between particles, gases are easily compressed.

GasesGases

The word The word vaporvapor refers to refers to the gaseous state of a the gaseous state of a substance that is a solid or substance that is a solid or a liquid at room a liquid at room temperature.temperature.

For example, steam is a For example, steam is a vapor because at room vapor because at room temperature water exists temperature water exists as a liquid.as a liquid.

Gas StructureGas Structure





LawsLaws

Law of Conservation of MassLaw of Conservation of Mass

Lavoisier concluded that Lavoisier concluded that when a chemical reaction when a chemical reaction occurs, mass is neither occurs, mass is neither created nor destroyed but created nor destroyed but only changed.only changed.

Lavoisier’s conclusion Lavoisier’s conclusion became known as the became known as the law of conservation of law of conservation of mass.mass.

Law of Conservation of Mass Clip

Law of Conservation of MassLaw of Conservation of Mass

In this law – mass is neither created nor In this law – mass is neither created nor destroyed – it is conserveddestroyed – it is conserved

Basically that means what you start with Basically that means what you start with has to equal what you end withhas to equal what you end with

Mass Mass reactantsreactants = Mass = Mass productsproducts

ExampleExample

Lets say that you have 10.00 g of mercury Lets say that you have 10.00 g of mercury (II) oxide. It is placed into a flask and (II) oxide. It is placed into a flask and heated until it is converted into liquid heated until it is converted into liquid mercury and oxygen gas. If I get 9.26 g of mercury and oxygen gas. If I get 9.26 g of liquid mercury, how much oxygen gas was liquid mercury, how much oxygen gas was created?created?

ExampleExample

First you need to write the reaction in word formFirst you need to write the reaction in word form Mercury (II) oxide Mercury (II) oxide mercury + oxygen mercury + oxygen

Now place the amounts under the reactionNow place the amounts under the reaction Mercury (II) oxide Mercury (II) oxide mercury + oxygen mercury + oxygen (10.00 g) = (9.26 g) + x(10.00 g) = (9.26 g) + x

Solve for xSolve for x X = 0.74 g of oxygen gasX = 0.74 g of oxygen gas

Try this one…Try this one…

A reaction between sodium hydroxide and A reaction between sodium hydroxide and hydrogen chloride gas produces sodium hydrogen chloride gas produces sodium chloride and water. A reaction of 22.85 g chloride and water. A reaction of 22.85 g of sodium hydroxide with 20.82 g of of sodium hydroxide with 20.82 g of hydrogen chloride gives off 10.29 g of hydrogen chloride gives off 10.29 g of water. What mass of sodium chloride is water. What mass of sodium chloride is formed in the reaction?formed in the reaction?

33.38 g sodium chloride

Here’s one that’s a little different…Here’s one that’s a little different…

Copper sulfide is formed when copper & Copper sulfide is formed when copper & sulfur are heated together. In this reaction sulfur are heated together. In this reaction 127 g of copper react with 41 g of sulfur. 127 g of copper react with 41 g of sulfur. After the reaction is complete, 9 g of sulfur After the reaction is complete, 9 g of sulfur remains un reacted. How much copper remains un reacted. How much copper sulfide was formed?sulfide was formed?

ExampleExample

First you need to write the reaction in word formFirst you need to write the reaction in word form Copper + sulfur Copper + sulfur copper sulfide copper sulfide

Now place the amounts under the reactionNow place the amounts under the reaction Copper + sulfur Copper + sulfur copper sulfide copper sulfide 127g + 127g + what goes here?what goes here? = x = x 127g + 32g = x127g + 32g = x

Solve for xSolve for x X = 159 g of copper sulfideX = 159 g of copper sulfide

Law of Definite ProportionsLaw of Definite Proportions

The elements that composed the The elements that composed the compounds were always in a certain compounds were always in a certain proportion by mass. proportion by mass.

This principle is now referred to as the This principle is now referred to as the law law of definite proportions.of definite proportions.

Another way to say this is…water is Another way to say this is…water is always water is always water…always water is always water…

The mass of the compound is equal to the The mass of the compound is equal to the sum of the masses of the elements that sum of the masses of the elements that make up the compound. make up the compound.

The ratio of the mass of each element to The ratio of the mass of each element to the total mass of the compound is a the total mass of the compound is a percentage called the percentage called the percent by masspercent by mass..

Law of Definite ProportionsLaw of Definite Proportions

ExampleExample

A compound is analyzed in the lab an A compound is analyzed in the lab an found to contain 8.44 g C, 1.3 g H, and found to contain 8.44 g C, 1.3 g H, and 10.26 g O. What is the % composition of 10.26 g O. What is the % composition of each element in the compound?each element in the compound?

First we must find the total massFirst we must find the total mass

% = Part x 100 Whole

ExampleExample

C = 8.44 gC = 8.44 g

H = 1.30 gH = 1.30 g

O = O = 10.26 g10.26 g

Total = 20.00gTotal = 20.00g

Now find the % of each

/ 20.00 g/ 20.00 g/ 20.00g

X 100 =X 100 =X 100 =

42.2% C6.50% H51.30% O

We find that this compound is sucrose

Another ExampleAnother Example

Now let’s say that Mr. Romano finds a Now let’s say that Mr. Romano finds a mystery white powder in the cafeteria. He mystery white powder in the cafeteria. He asks us to analyze the substance and tell asks us to analyze the substance and tell him what it is.him what it is.

We find that there is 211.0 g of C, 32.5 g We find that there is 211.0 g of C, 32.5 g H, and 256.5 g O. What is the % H, and 256.5 g O. What is the % composition of the compound?composition of the compound?

Another ExampleAnother Example

C = 211.0 gC = 211.0 g

H = 32.5 gH = 32.5 g

O = O = 256.5 g256.5 g

Total = 500.00gTotal = 500.00g

/ 500.00 g/ 500.00 g/ 500.00g

X 100 =X 100 =X 100 =

42.2% C6.50% H51.30% O

What is the mystery white powder???

SUCROSE

The The law of multiple proportionslaw of multiple proportions states that states that when different compounds are formed by a when different compounds are formed by a combination of the same elements, different combination of the same elements, different masses of one element combine with the masses of one element combine with the same relative mass of the other element in a same relative mass of the other element in a ratio of small whole numbers. ratio of small whole numbers.

Ratios compare the relative amounts of any Ratios compare the relative amounts of any items or substances. items or substances.

Law of Multiple ProportionsLaw of Multiple Proportions

The two distinct compounds water (HThe two distinct compounds water (H22O) and O) and hydrogen peroxide (Hhydrogen peroxide (H22OO22) illustrate the law of ) illustrate the law of multiple proportions. multiple proportions.

Both water & hydrogen peroxide are made up of Both water & hydrogen peroxide are made up of hydrogen and oxygen, the difference is in their hydrogen and oxygen, the difference is in their proportions.proportions.

When we compare the mass of oxygen in When we compare the mass of oxygen in hydrogen peroxide to the mass of oxygen in hydrogen peroxide to the mass of oxygen in water, we get the ratio 2:1.water, we get the ratio 2:1.

Law of Multiple ProportionsLaw of Multiple Proportions

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