Updated February 2006 Created by C. IppolitoSeptember 2003

Chemistry Is Everywhere

Objectives:Distinguish between pure (research) science and applied (research) science or technology

Explain the scientific method

Appreciate the roots of chemistry

Updated February 2006 Created by C. IppolitoSeptember 2003

Science

• explaining how and why things are as they are– Pure Science (Research) Pure Science (Research)

• search for knowledge for its own sake

– Applied Science (Research) Applied Science (Research) • use knowledge improve the quality of life

– use knowledge to benefit– limiting any harmful effects

Updated February 2006 Created by C. IppolitoSeptember 2003

Chemis-tree

AlchemyAlchemy

Inorganic Inorganic ChemistryChemistry

AnalyticalAnalytical ChemistryChemistry

Organic Organic ChemistryChemistry

BiochemistryBiochemistry

Physical Physical ChemistryChemistry

Updated February 2006 Created by C. IppolitoSeptember 2003

Chemistry• studies and investigates the structure and

properties of matter – AlchemyAlchemy

• early studies to find “elixir of life” and the “philosopher’s stone” which could change base metals into gold

– BiochemistryBiochemistry• biologically active matter (food, drugs, hormones)

– Inorganic ChemistryInorganic Chemistry• carbonless substances (metals, ores, glass)

– Organic ChemistryOrganic Chemistry• carbon substances natural & synthetic (polymers, textiles)

– Physical ChemistryPhysical Chemistry• physical properties and relationship to energy/matter

– Analytical ChemistryAnalytical Chemistry• develops procedures used to analyze matter

Updated February 2006 Created by C. IppolitoSeptember 2003

Ancient Greek Philosophers

• explain natural world– use reasoning and logic

• AristotleAristotle– Matter made of FOUR elements:

» earth, air, fire, water– Elements change with exposure to:

» heat, cold, dampness, dryness– Caloric

» substance that “flowed” from hot bodies to cold bodies

Updated February 2006 Created by C. IppolitoSeptember 2003

Alchemy

• Ancients try to change lead into gold

• the study of behavior of matter from 3rd century BC– ChemeiaChemeia (GR) to transmute or change

matter

Updated February 2006 Created by C. IppolitoSeptember 2003

Prominent Arab Alchemists

• Al-Geber Al-Geber (721-815) “father of Arab chemistry”– emphasized systematic experimentation

• wrote detailed “recipes”• “gibberish” derived from his name

• Al-RaziAl-Razi (864-930)

– discovered alcohol and sulfuric acid

Updated February 2006 Created by C. IppolitoSeptember 2003

13 -14th Century Europeans

• Rediscovered the ancient texts

– transmutation• change “base” metals into GOLDGOLD

• Experiments built body of knowledge:

– MetallurgyMetallurgy • Extraction of metals from ore

Updated February 2006 Created by C. IppolitoSeptember 2003

17th Century Europe

• Matter made of THREE (3) elements (earths)– vitreous earthvitreous earth – solidity of matter– fluid earthfluid earth – liquidity of matter– fatty earthfatty earth (phlogiston) – combustibility to

matter

• Same as Aristotle w/o air –now “inert”

Updated February 2006 Created by C. IppolitoSeptember 2003

The “Science of Chemistry”

• Van HelmontVan Helmont– Distinct gases make up air

• Robert BoyleRobert Boyle – Gas laws

• Volume and pressure vary inversely

Updated February 2006 Created by C. IppolitoSeptember 2003

Scientific Method• Organized procedures

used to solve problems / gain knowledge

1. state problem

2. collect observations

3. form hypothesis

4. test hypothesis

5. form conclusion

6. form theory

7. modify theory

Updated February 2006 Created by C. IppolitoSeptember 2003

Test Hypothesis• controlled experiment

– consists of two groups:• Experimental GroupExperimental Group

– independent variable causes an observable difference (effect) in dependent variable

– If independent variable then dependent variable

• Control GroupControl Group– identical to experimental group except:

» does not contain the independent variable– used for comparison – verifies affect of the independent variable

Updated February 2006 Created by C. IppolitoSeptember 2003

Theory

• general explanation– fits many different observations

• made by many different scientists– supported by repeated experimental evidence– over a long period of time

• explanation unifies understanding