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Chapter 1Chapter 1Introduction to Introduction to

ChemistryChemistry

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1.1 What is Chemistry?1.1 What is Chemistry? Chemistry is the study of the Chemistry is the study of the

composition of composition of ““mattermatter”” – (matter is – (matter is anything with mass and occupies anything with mass and occupies space), its composition, properties, and space), its composition, properties, and the changes it undergoes.the changes it undergoes.

Has a definite affect on everyday life - Has a definite affect on everyday life - taste of foods, grades of gasoline, etc.taste of foods, grades of gasoline, etc.

Living and nonliving things are made of Living and nonliving things are made of matter.matter.

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5 Major Areas of Chemistry5 Major Areas of Chemistry1)1) Analytical ChemistryAnalytical Chemistry- concerned with - concerned with

the composition of substances.the composition of substances.2)2) Inorganic ChemistryInorganic Chemistry- primarily deals - primarily deals

with substances without carbonwith substances without carbon3)3) Organic ChemistryOrganic Chemistry- essentially all - essentially all

substances containing carbonsubstances containing carbon4)4) BiochemistryBiochemistry- Chemistry of living things- Chemistry of living things5)5) Physical ChemistryPhysical Chemistry- describes the - describes the

behavior of chemicals (ex. stretching); behavior of chemicals (ex. stretching); involves lots of math!involves lots of math!

Boundaries not firm – they overlap and interact.Boundaries not firm – they overlap and interact.

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What is Chemistry?What is Chemistry? Pure Chemistry-Pure Chemistry- gathers knowledge for gathers knowledge for

the the sake of knowledge.sake of knowledge. Applied Chemistry-Applied Chemistry- is using chemistry is using chemistry

to to attain certain goalsattain certain goals, in fields like , in fields like medicine, agriculture, and medicine, agriculture, and manufacturing – leads to an application.manufacturing – leads to an application.– * Nylon – Figure 1.3, page 9* Nylon – Figure 1.3, page 9

* Aspirin (C* Aspirin (C99HH88OO44) - to relieve pain) - to relieve pain

* Use of TECHNOLOGY * Use of TECHNOLOGY (benefit!)(benefit!)

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Why Study Chemistry?Why Study Chemistry? Everyone and everything around us Everyone and everything around us

involves chemistry – explains our worldinvolves chemistry – explains our world What isnWhat isn’’t Chemistry?t Chemistry? Helps you make choices; helps make Helps you make choices; helps make

you a better informed citizen.you a better informed citizen. A possible career for your future.A possible career for your future. Used to attain a specific goal.Used to attain a specific goal.

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1.2 Chemistry Far and Wide1.2 Chemistry Far and Wide Chemists design materials to fit Chemists design materials to fit

specific needs, ex. velcro specific needs, ex. velcro (Patented in (Patented in

1955), 1955), Kevlar, Kevlar, Perfume, steel, ceramics, plastics, Perfume, steel, ceramics, plastics,

rubber, paints, nonstick cooking rubber, paints, nonstick cooking utensils, polyester fibers.utensils, polyester fibers.

2 different ways to look at the 2 different ways to look at the world: Macroscopic and world: Macroscopic and Microscopic.Microscopic.

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Chemistry Far and WideChemistry Far and Wide Energy – we constantly have Energy – we constantly have

greater demands.greater demands.

–We must conserve and use it We must conserve and use it wisely.wisely.

–We can try to produce more; oil We can try to produce more; oil from soybeans to make biodieselfrom soybeans to make biodiesel

–Fossil fuels, solar, batteries, wind, Fossil fuels, solar, batteries, wind, and nuclear.and nuclear.

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Chemistry Far and WideChemistry Far and WideMedicine and Biotechnology-Medicine and Biotechnology-

–Supply materials doctors use to Supply materials doctors use to treat patients.treat patients.

–Vitamin C, Penicillin, Aspirin.Vitamin C, Penicillin, Aspirin.

–Materials for artery transplants Materials for artery transplants and joint replacements.and joint replacements.

–Bacteria producing insulin.Bacteria producing insulin.

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Chemistry Far and WideChemistry Far and Wide AgricultureAgriculture

–Produce the worldProduce the world’’s food supply.s food supply.

–Use chemistry for better Use chemistry for better productivity – soil, water, weeds.productivity – soil, water, weeds.

–Plant growth hormones.Plant growth hormones.

–Ways to protect crops; Ways to protect crops; insecticides.insecticides.

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Chemistry Far and WideChemistry Far and Wide EnvironmentEnvironment

–Both risks and benefits involved in Both risks and benefits involved in discoveries; Fracking.discoveries; Fracking.

–Pollutants need to be 1) identified Pollutants need to be 1) identified and 2) prevented.and 2) prevented.

–Lead paint was prohibited in 1978; Lead paint was prohibited in 1978; Leaded gasoline? Drinking water?Leaded gasoline? Drinking water?

–Carbon dioxide, ozone, global Carbon dioxide, ozone, global warming.warming.

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Chemistry Far and WideChemistry Far and WideThe UniverseThe Universe

–Need to gather data from afar, Need to gather data from afar, and analyze matter brought back and analyze matter brought back to Earth.to Earth.

–Composition of the planets.Composition of the planets.–Analyze Mars and moon rocks.Analyze Mars and moon rocks.–Planet atmospheres.Planet atmospheres.–Life on other planets?Life on other planets?

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1.3 Alchemy1.3 Alchemy – – Developed the Developed the tools tools and techniquesand techniques for working with for working with

chemicals.chemicals. Alchemy has 2 sides:Alchemy has 2 sides:

–Practical: Practical: TechniquesTechniques for working for working with metals, glass, dyes, etc.with metals, glass, dyes, etc.

–Mystical: Mystical: ConceptsConcepts like perfection – like perfection – gold was a perfect metal. gold was a perfect metal.

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LavoisierLavoisier In the late 1700s, In the late 1700s, Antoine Antoine

LavoisierLavoisier helped transform helped transform chemistry from a chemistry from a science of science of observationobservation to the to the science of science of measurementmeasurement – still used today. – still used today.

He settled a long-standing debate He settled a long-standing debate about burning, which was…about burning, which was…

–OxygenOxygen was required! was required!

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The Scientific MethodThe Scientific Method A logical approach to solving A logical approach to solving

problems or answering questions.problems or answering questions.

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Steps in the Scientific MethodSteps in the Scientific Method1. Observations (uses your senses)1. Observations (uses your senses)

a)a) QuantitativeQuantitative involves numbers = involves numbers = 9595ooFF

b)b) QualitativeQualitative is word description = hot is word description = hot2. Formulating Hypotheses (ideas)2. Formulating Hypotheses (ideas)

- - Possible explanation for the Possible explanation for the observation, or observation, or ““educatededucated”” guess. guess.

3. Performing Experiments (the test)3. Performing Experiments (the test)- - Gathers new information to help Gathers new information to help

decide whether the hypothesis is valid.decide whether the hypothesis is valid.

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Scientific MethodScientific Method We deal with We deal with VariablesVariables, or factors that can , or factors that can

change. 2 types:change. 2 types:

1) 1) Manipulated VariableManipulated Variable (or Independent (or Independent Variable) is the one that Variable) is the one that wewe change. change.

2) 2) Responding VariableResponding Variable (or Dependent (or Dependent Variable) is the one observed during the Variable) is the one observed during the experiment.experiment.

For results to be accepted, the experiment For results to be accepted, the experiment needs to always produce the same result.needs to always produce the same result.

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Outcomes over the long term…Outcomes over the long term… TheoryTheory (Model) (Model) ““whatwhat””

- - A set of A set of well-testedwell-tested hypotheses that gives hypotheses that gives an overall an overall EXPLANATIONEXPLANATION of some natural of some natural phenomenon – phenomenon – not able to be provednot able to be proved..

Natural LawNatural Law (or Scientific Law) (or Scientific Law) ““whywhy””

- - The same observation applies to manyThe same observation applies to many different systems; different systems; summarizessummarizes results. results.

- - an example would be: Law of an example would be: Law of Conservation of Mass.Conservation of Mass.

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Using your senses to obtain information

Hypothesis is a proposed Explanation; should be based on previous knowledge; an “educated” guess.

The procedure that is used to test the Hypothesis

A well-tested Explanation for the observations; cannot be proven due to new discoveries.

Tells what happened

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Collaboration / CommunicationCollaboration / Communication When scientists share ideas by When scientists share ideas by

Collaboration and Communication, Collaboration and Communication, they they increase the likelihoodincrease the likelihood of a of a successful outcome.successful outcome.

Collaboration –How is Collaboration –How is communication done?communication done?

Is the Internet reliable information?Is the Internet reliable information?

–http://www.dhmo.orghttp://www.dhmo.org

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1.4 Problem Solving in Chemistry1.4 Problem Solving in Chemistry Effective problem solving usually Effective problem solving usually

involves 2 general steps:involves 2 general steps:1)1) Developing a plan.Developing a plan.2)2) Implementing that plan.Implementing that plan.

The skills you use to solve a word The skills you use to solve a word problem in chemistry are NOT problem in chemistry are NOT different from those techniques different from those techniques used in shopping, cooking, or used in shopping, cooking, or planning a party.planning a party.

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Solving Numeric ProblemsSolving Numeric Problems The 3 steps we will use for solving a The 3 steps we will use for solving a

numeric word problem are:numeric word problem are:

1)1) AAnalyzenalyze

2)2) CCalculatealculate

3)3) EEvaluatevaluate

Let’s learn how

to ACE these numeric word problems!

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Solving Numeric ProblemsSolving Numeric Problems1)1) AnalyzeAnalyze:: this is the starting point this is the starting point

– Determine what are the Determine what are the Known factorsKnown factors, , and write them down on your paper!and write them down on your paper!

– Determine what is the Determine what is the UnknownUnknown. If it is . If it is a number, determine the a number, determine the UnitsUnits needed. needed.

– Plan how to relate these factors- Plan how to relate these factors- choose an equation, use table or graph.choose an equation, use table or graph.

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Solving Numeric ProblemsSolving Numeric Problems2)2) Calculate:Calculate: perform the mathematicsperform the mathematics

– If your plan is correct, this is the If your plan is correct, this is the easiest step. easiest step.

– Calculator? Use it correctly!Calculator? Use it correctly!

– May involve May involve rearrangingrearranging an an equation algebraically; or, doing equation algebraically; or, doing some some conversionconversion of units to some of units to some other units.other units.

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Solving Numeric ProblemsSolving Numeric Problems3)3) Evaluate:Evaluate: – the finishing step – the finishing step

– Is it reasonable? Make sense? Is it reasonable? Make sense? Do an estimate for the answer, Do an estimate for the answer, and check your calculations.and check your calculations.

– Need to round off the answer?Need to round off the answer?– Do you need Scientific Notation?Do you need Scientific Notation?– Do you have the correct units?Do you have the correct units?– Did you Did you answer the questionanswer the question??

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Solving Conceptual ProblemsSolving Conceptual Problems Not all word problems in chemistry Not all word problems in chemistry

involve doing calculations.involve doing calculations. Nonnumeric problems are called Nonnumeric problems are called

Conceptual ProblemsConceptual Problems – ask you to apply – ask you to apply concepts to a new situationconcepts to a new situation

Steps are:Steps are:1)1) AnalyzeAnalyze2)2) SolveSolve

Plan needed to link known to unknown.Plan needed to link known to unknown.