Chemistry Honors Chemistry Honors

Matter and Change Matter and Change &&

ElementsElements

Chemistry –

the study of the composition of matter and the changes it undergoesThere are 5 main branches of

chemistry:Organic -

The study of compounds that contain carbon

Inorganic -

Biochemistry - Analytical - Physical -

The study of the composition of matter

The study of chemical processes which take place in organisms

The study of compounds which, in general, do not

The study of reaction rates and mechanisms, as well as the energy transfer which occurs during a reaction

Pure vs. AppliedPure vs. Applied Pure Chemistry – the pursuit of chemical Pure Chemistry – the pursuit of chemical

knowledge for its own sakeknowledge for its own sake The chemist doesnThe chemist doesn’’t expect that there will be any t expect that there will be any

immediate practical use for the knowledge.immediate practical use for the knowledge. Ex. – Studying the composition of desks.Ex. – Studying the composition of desks.

Applied Chemistry – research that is directed Applied Chemistry – research that is directed toward a practical goal or application.toward a practical goal or application. The chemist is applying what they have The chemist is applying what they have

researched to solve a problem, produce a researched to solve a problem, produce a product, etc.product, etc.

Ex. – Testing the effectiveness of certain drugs on Ex. – Testing the effectiveness of certain drugs on the H1N1 virus.the H1N1 virus.

Chemical TechnologyChemical Technology

Technology is the means by which a Technology is the means by which a society provides its members with society provides its members with those things needed and desired.those things needed and desired. Allows humans to do some things more Allows humans to do some things more

quickly or with less effort.quickly or with less effort. It allows people to do things that would It allows people to do things that would

otherwise be impossible.otherwise be impossible.

Chemical ElementsChemical Elements The simplest form in which a substance The simplest form in which a substance

exists. Cannot be broken down by a exists. Cannot be broken down by a chemical reaction.chemical reaction.

91 occur naturally, the rest are man 91 occur naturally, the rest are man made. made.

Colors on the periodic table are Colors on the periodic table are determined by state at room temperature.determined by state at room temperature.

Each is represented by a one or two-letter Each is represented by a one or two-letter symbol. First letter is capitalized, second symbol. First letter is capitalized, second is lower case.is lower case.

Some Elements are named Some Elements are named after a propertyafter a property

Au: Latin aurum – Au: Latin aurum – shining dawnshining dawn

Br: Greek bromos – Br: Greek bromos – stenchstench

H: hydros genes – H: hydros genes – water born (water water born (water former)former)

Some are named after the Some are named after the location of discoverylocation of discovery

Indium (In)Indium (In) Francium (Fr)Francium (Fr) Germanium (Ge)Germanium (Ge) Californium (Cf)Californium (Cf) Helium (He)Helium (He)

Others are also named for a Others are also named for a celestial bodycelestial body

Tellurium (Te)Tellurium (Te)

Mercury (Hg)Mercury (Hg)

Uranium (U)Uranium (U)

Still others were named Still others were named after famous scientists.after famous scientists.

Nobelium (No)Nobelium (No)

Curium (Cm)Curium (Cm)

Einsteinium (Es)Einsteinium (Es)

Names for the elements have Names for the elements have their origins in several languages:their origins in several languages:Latin,Latin, Olde

English,even Arabic

Most of the symbols we use come from the Most of the symbols we use come from the English or Latin names. Some examples of English or Latin names. Some examples of symbols derived from the Latin include:symbols derived from the Latin include:

Au - gold Ag - silver

Cu - copper Pb - lead

There is one symbol, however, that does not come from English or Latin.

W - tungsten

The W is from wolfram, the German word for tungsten.

The metal is found in the mineral known as wolframite.

The Scientific MethodThe Scientific Method

A A processprocess of studying natural of studying natural phenomena that involves making phenomena that involves making observations, forming laws and theories, observations, forming laws and theories, and testing theories by experimentationand testing theories by experimentation

Effective problem solving involves Effective problem solving involves developing and implementing a plan.developing and implementing a plan.

Science is a dynamic and self-correcting Science is a dynamic and self-correcting and it involves a certain process, or and it involves a certain process, or method.method.

Science as a ProcessScience as a Process

Observation

direct indirect

Hypothesis(Testable explanation for a set of observations)

Experiment(Controlled as much as possible – variables: independent - manipulated, dependent – responding)

(Example – reaction time (dependent) vs. temperature (independent))

Science as a ProcessScience as a Process

Yes No

Theory New hypothesis(Well-tested explanation for a broad set of observations)

Law

Relate

verification

While science involves a process, it is also very often influenced by serendipity.

(Summarizes the results of many observations)

The Difference Between a Theory The Difference Between a Theory and a Lawand a Law

Laws Laws predict whatpredict what will happen will happen

Theories Theories explainexplain whywhy something something happenshappens Which will also allow you to predict Which will also allow you to predict

what will happen!what will happen!

MatterMatter

Something that has mass and takes up Something that has mass and takes up space (volume)space (volume)

5 different states of matter:5 different states of matter: Solid – definite shape and volumeSolid – definite shape and volume Liquid – definite volume, indefinite shapeLiquid – definite volume, indefinite shape Gas – indefinite shape and volumeGas – indefinite shape and volume

Gas & vapor are NOT the same thingGas & vapor are NOT the same thing Vapor describes the gaseous state of a substance Vapor describes the gaseous state of a substance

that is usually a liquid or solid at room tempthat is usually a liquid or solid at room temp Plasma – very hot, electrons stripped awayPlasma – very hot, electrons stripped away Bose – Einstein condensate – at very low Bose – Einstein condensate – at very low

temperaturestemperatures

Classifying MatterClassifying Matter

Matter

Pure Substance

Element Compound

Mixture

Heterogeneous Homogeneous

Phase – term used to describe any part of a sample with a uniform composition and properties.

(solution)

SeparationSeparation

Mixtures and pure substances can Mixtures and pure substances can be separated using be separated using physicalphysical methods.methods.

Examples: filtration, distillation, Examples: filtration, distillation, evaporationevaporation

Elements and compounds can be Elements and compounds can be separated using separated using chemicalchemical methods methods (reactions)(reactions)

Properties of MatterProperties of Matter Properties used to describe matter Properties used to describe matter

can be classified as extensive or can be classified as extensive or intensive.intensive.

Intensive Properties – depends on the Intensive Properties – depends on the type of matter present, not the amounttype of matter present, not the amount density, malleability, conductivity, density, malleability, conductivity,

ductility, luster, mp, bp, color, tempductility, luster, mp, bp, color, temp Extensive Properties – depends on the Extensive Properties – depends on the

amount of matter in a sampleamount of matter in a sample mass, length, volume, shape, sizemass, length, volume, shape, size

Most properties are INTENSIVEMost properties are INTENSIVE

Physical Physical Properties/ChangesProperties/Changes

Physical Property – quality or Physical Property – quality or condition of a substance that can be condition of a substance that can be observed or measured without observed or measured without changing the composition of that changing the composition of that substancesubstance odor, color, density, solubility, mp, bpodor, color, density, solubility, mp, bp metals – conductivity, malleability, metals – conductivity, malleability,

ductility, lusterductility, luster

Physical ChangePhysical Change

Physical Change – some properties Physical Change – some properties of the substance change, but the of the substance change, but the composition does not changecomposition does not change boil, freeze, melt, condense, break, boil, freeze, melt, condense, break,

split, cut, grindsplit, cut, grind

Chemical Chemical Properties/ChangesProperties/Changes

Chemical Property – the ability of a Chemical Property – the ability of a substance to undergo a change in substance to undergo a change in compositioncomposition rust, burn, rot, decompose, ferment, rust, burn, rot, decompose, ferment,

explode, corrodeexplode, corrode Chemical Change – the composition Chemical Change – the composition

of matter always changesof matter always changes Deciding between a physical & Deciding between a physical &

chemical change, ask yourself if you chemical change, ask yourself if you can get back what you started with.can get back what you started with. Answer YES – physical changeAnswer YES – physical change Answer NO – chemical changeAnswer NO – chemical change

Chemical ReactionsChemical Reactions

One or more substances turn into one or One or more substances turn into one or more new substances.more new substances. Mass is always conserved – Law of Conservation Mass is always conserved – Law of Conservation

of Massof Mass Reactant – substance present at the Reactant – substance present at the

beginningbeginning Product – substance present at the endProduct – substance present at the end Evidence of a chemical change:Evidence of a chemical change:

Evolution of a gasEvolution of a gas Formation of a precipitate (ppt)Formation of a precipitate (ppt) Color changeColor change Evolution of heat/transfer of energyEvolution of heat/transfer of energy Odor producedOdor produced

PracticePractice Identify the following as element, Identify the following as element,

heterogenous mixture, or homogeneous heterogenous mixture, or homogeneous mixture:mixture: Rubbing alcoholRubbing alcohol Ice waterIce water PennyPenny PaintPaint PaperPaper InkInk BrassBrass Al foilAl foil SalsaSalsa

PracticePractice

Decide if the following are a chemical Decide if the following are a chemical or physical change:or physical change: Color fadesColor fades Digest lunchDigest lunch Cutting paperCutting paper Plant growsPlant grows Cloud formationCloud formation Turn on flashlightTurn on flashlight Ice meltsIce melts Wound healsWound heals Fry an eggFry an egg

PracticePractice

Classify as intensive or extensive Classify as intensive or extensive property:property: ConductivityConductivity VolumeVolume DensityDensity ColorColor TemperatureTemperature Heat contentHeat content