Ch 1 Matter and Change 1.1 Chemistry is a Physical Science Chemistry is the study of matter (composition, structure, properties) and processes Branches of chemistry: Organic-study of all chemicals containing carbon Inorganic-chemicals not containing carbon Analytical-composition of matter Physical- mechanism, rate, energy transfer of matter undergoing change Biochemistry- study of processes taking place with organisms Theoretical- use math/comp understand principles

Basic Research: to increase scientific knowledge Applied Research: to solve a problem Technological Developments: production and use of products to improve quality of life See chemistry in: Medicine- medicines, materials, technology Biotechnology-production of biological products/ processes Agriculture-develop more productive crops, safer/effective ways to protect crops Environment- identify and prevent pollutants Universe- gather data and bring it back to Earth

Thinking like a scientist (we all do!!) History: chemistry came from alchemy Alchemists developed tools and techniques for working with chemicals Lavisier transformed science with creation of balance Experiments: Manipulated (independent) vs Dependent (responding variable) Scientific method: observations, making hypothesis, experimentation, developing theories/laws, communicating findings Collaboration- working together/ sharing ideas

1.2 Matter and Its Properties Atom: smallest unit to ID  element: pure substance cannot be broken down Combining 2+elements/atoms compound Solid (desk), Liquid (water), Gas (He), Plasma (lightening) All substances have properties Extensive: depends on amount; volume, mass, amount of energy Intensive: depends on type/composition (not the amount); melting point, boiling point, density, conduct electricity, transfer heat energy

Physical Properties: obs/ID without changing composition Physical change: cutting, grinding, melting, boiling, phase changes Change in state: solid, liquid, gas, plasma Chemical Properties: changes composition Chemical change: reactants products, change chemical composition Evidence of chemical change: gas produced, temp change, precipitate formed, color change, odor produced

Pure substances: fixed composition Every sample: has same characteristic properties and exactly same composition Mixtures: 2+ matter blended together Heterogeneous: no uniform Homogeneous (aka solution): uniform composition

1.3 Elements Periodic table is organized by chemical properties Groups (columns) Similar chem comp 1-18 Periods (rows) Repeating patterns 1-7

Metals Nonmetals Metalloids Characteristics: shininess/metallic luster, conduct electricity and heat well, malleable, ductile (make fine wire), high tensile strength (resist breaking) Nonmetals Characteristics: gas or solid at room temp, brittle, poor conductor of electricity and heat Group 18 noble gases: low reactivity, full e- shells Metalloids Characteristics: solids at room temp, less malleable/not as brittle, some have luster, semiconductors of electricity