Introduction to Introduction to ChemistryChemistry

Chapter 1Chapter 1Dr. YagerDr. Yager

Matter and ChemistryMatter and Chemistry

MatterMatter is anything that has mass and occupies space. is anything that has mass and occupies space.

ChemistryChemistry is the study of the composition of matter is the study of the composition of matter and the changes that matter undergoes.and the changes that matter undergoes.

Five Traditional Areas of ChemistryFive Traditional Areas of Chemistry

Organic chemistryOrganic chemistry

Inorganic chemistryInorganic chemistry

Biochemistry Biochemistry

Analytical chemistryAnalytical chemistry

Physical chemistryPhysical chemistry

Organic chemistryOrganic chemistry is defined as the is defined as the study of all chemicals study of all chemicals containing carbon.containing carbon.

Inorganic chemistryInorganic chemistry is is the study of chemicals the study of chemicals that, in general, do not that, in general, do not contain carbon.contain carbon.

Adult bone is 5% living cells, 95% Adult bone is 5% living cells, 95% non-living material. About 30% of non-living material. About 30% of bone by dry weight is organic, while bone by dry weight is organic, while the rest is inorganic (minerals).the rest is inorganic (minerals).

The study of The study of processes that processes that take place in take place in organisms is organisms is biochemistrybiochemistry..

Analytical Analytical chemistrychemistry is is the study of the the study of the composition of composition of matter.matter.

Physical Physical chemistrychemistry deals deals with the with the mechanism, the mechanism, the rate, and the rate, and the energy transfer energy transfer that occurs when that occurs when matter undergoes matter undergoes a change.a change.

Pure and Applied ChemistryPure and Applied Chemistry

Pure chemistryPure chemistry is the pursuit of chemical is the pursuit of chemical knowledge for its own sake.knowledge for its own sake.

Applied chemistryApplied chemistry is research that is is research that is directed toward a practical goal or directed toward a practical goal or application.application.

Chemists Design MaterialsChemists Design Materials

In 1948, George de Mestral In 1948, George de Mestral took a close look at the burrs took a close look at the burrs that stuck to his clothing. He that stuck to his clothing. He saw that each burr was saw that each burr was covered with many tiny covered with many tiny hooks. hooks.

In 1955, de Mestral patented In 1955, de Mestral patented the design for the hook-and-the design for the hook-and-loop tapes. These are used loop tapes. These are used as fasteners in shoes and as fasteners in shoes and gloves.gloves.

SEAgelSEAgel is a modern is a modern insulation that is light insulation that is light enough to float on soap enough to float on soap bubbles.bubbles.

One of the easiest ways to conserve energy is One of the easiest ways to conserve energy is through insulation. Insulation acts as a barrier to through insulation. Insulation acts as a barrier to heat flow from the inside to the outside of a house or heat flow from the inside to the outside of a house or from the outside to the inside of a freezer.from the outside to the inside of a freezer.

Chemists also help Chemists also help determine when a crop determine when a crop needs water. needs water.

If the genes from a jellyfish If the genes from a jellyfish that glows are transferred that glows are transferred to a potato plant, the plant to a potato plant, the plant glows when it needs to be glows when it needs to be watered.watered.

Chemists sometimes use chemicals Chemists sometimes use chemicals produced by insects to fight insect pests. produced by insects to fight insect pests. The plastic tube wrapped around the stem The plastic tube wrapped around the stem of the tomato plant contains a chemical of the tomato plant contains a chemical that a female pinworm moth emits to that a female pinworm moth emits to attract male moths. It interferes with the attract male moths. It interferes with the mating process so that fewer pinworms mating process so that fewer pinworms are produced.are produced.

Until the mid-1900s, lead was used in many Until the mid-1900s, lead was used in many products, including paints and gasoline.products, including paints and gasoline. In 1971, a study showed that the level of lead that is In 1971, a study showed that the level of lead that is harmful to humans is much lower than previously harmful to humans is much lower than previously thought, especially for children. Even low levels of lead thought, especially for children. Even low levels of lead in the blood can permanently damage the nervous in the blood can permanently damage the nervous system of a growing child.system of a growing child.

Chemists have analyzed more than 850 pounds Chemists have analyzed more than 850 pounds of moon rocks that were brought back to Earth. of moon rocks that were brought back to Earth. Some of these rocks are similar to rocks formed Some of these rocks are similar to rocks formed by volcanoes on Earth, suggesting that vast by volcanoes on Earth, suggesting that vast oceans of molten lava once covered the moon's oceans of molten lava once covered the moon's surface.surface.

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Before Chemists Before Chemists

There Were Alchemists There Were Alchemists

Alchemists wanted to turn lead to gold.Alchemists wanted to turn lead to gold.

They wanted to do other magic tricks like They wanted to do other magic tricks like create life.create life.

Alchemists developed Alchemists developed processes for separating processes for separating mixtures and purifying mixtures and purifying chemicals. They designed chemicals. They designed equipment that is still in use equipment that is still in use today including beakers, today including beakers, flasks, tongs, funnels, and flasks, tongs, funnels, and the mortar and pestle.the mortar and pestle.

Alchemists’ ContributionAlchemists’ Contribution

Antoine-Laurent LavoisierAntoine-Laurent Lavoisier

Father of modern chemistryFather of modern chemistry Transformed chemistry from a science of Transformed chemistry from a science of

observation to the science of measurement observation to the science of measurement (0.0005 gm scale)(0.0005 gm scale)

Showed that oxygen is required for a material Showed that oxygen is required for a material to burn using the scientific methodto burn using the scientific method

Beheaded during the French RevolutionBeheaded during the French Revolution

Scientific MethodScientific Method

A logical, systematic approach to the A logical, systematic approach to the solution of a scientific problemsolution of a scientific problem

Steps Include:Steps Include: making observations making observations doing experimentsdoing experiments testing hypothesestesting hypotheses developing theoriesdeveloping theories

AnAn experimentexperiment is a procedure that is is a procedure that is used to test a hypothesis. When you used to test a hypothesis. When you design experiments, you deal with design experiments, you deal with variables, or factors that can change.variables, or factors that can change.

• The variable that you change during an The variable that you change during an experiment is the experiment is the manipulated variablemanipulated variable, or , or independent variableindependent variable..

• The variable that is observed during the The variable that is observed during the experiment is the experiment is the responding variableresponding variable, or , or dependent variabledependent variable..

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TheoryTheory

Once a hypothesis meets the test of repeated Once a hypothesis meets the test of repeated experimentation, it may become a theory.experimentation, it may become a theory.

A A theorytheory is a well-tested explanation for a is a well-tested explanation for a broad set of observations.broad set of observations.

A theory may need to be changed at some A theory may need to be changed at some point in the future to explain new observations point in the future to explain new observations or experimental results.or experimental results.

Scientific LawScientific Law

A A scientific lawscientific law is a concise statement that is a concise statement that summarizes the results of many observations summarizes the results of many observations and experiments. and experiments.

A scientific law doesn’t try to explain the A scientific law doesn’t try to explain the relationship it describes. That explanation relationship it describes. That explanation requires a theory.requires a theory.

Steps in the Scientific MethodSteps in the Scientific Method

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““Real” ScienceReal” Science

Run another test to get results

“journal ready”

Notice something interesting and

unexpected

Can’t Get Good ReadingsPower Goes out for an Hour

Machine Breaks

Go to conference, get distracted by new idea

Realize you don’t have tools to analyze results

Teaching undergrads, no time to find answers

Problem Solving in ChemistryProblem Solving in Chemistry

AnalyzeAnalyze

To solve a word problem, you must first determine where you are starting from (identify what is known) and where you are going (identify the unknown).

After you identify the known and the unknown, you need to make a plan for getting from the known to the unknown.

CalculateCalculate

If you make an effective plan, doing the calculations is usually the easiest part of the process.

EvaluateEvaluate

Check that your answer is reasonable and makes sense. Check that it has the correct units and the correct number of significant figures.

Practice ProblemPractice Problem

Conceptual ProblemsConceptual Problems

Homework?Homework?

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