Presentation on theme: "Chapters 1 & 2: Intro to Chemistry & Matter and Change"— Presentation transcript:
1 Chapters 1 & 2: Intro to Chemistry & Matter and Change What is chemistry?the study of the composition, structure, and properties of matter and the changes it undergoes.considers behaviors of materials as well.Branches of ChemistryOrganic chemistry: studies compounds composed of carbon.Inorganic chemistry: studies compounds that do not contain carbon.Physical chemistry: studies the relationship between energyand matter.Analytical chemistry: identifies the components and make-up ofmaterials.Biochemistry: studies the substances and processes involved inliving things.Theoretical chemistry: utilizes computers to design and predictthe properties of new substances.
2 Scientific methodMost scientific advances result from carefully planned investigation.Scientific methodObservingcollecting datameasuringFormulating Hypothesesanalyzing datapredictingTestingexperimentingcollecting dataIf data doesnot supporthypothesisTheorizingconstructing modelspredictingPublish Resultscommunicating
3 Scientific method Observing Making measurements and/or collecting data.Data can be either qualitative (descriptive/words) or quantitative (numerical).Formulating HypothesesA testable statement that serves as the basis for making predictions.Testing HypothesesExperiments are performed that provide data to support or refute a hypothesis.TheorizingWhen predictions of the hypothesis are successful, scientists use models (explanations of how phenomena occur and how events are related).Theories: a generalization that explains body of facts and phenomena.
4 solid: matter with a definite shape and definite volume. Change of StateboilingmeltingSolidLiquidGasfreezingCondensationsolid: matter with a definite shape and definite volume.liquid: matter with a definite volume but an indefinite shape.gas: matter without a definite shape or volume.Solid,Liquid,Gas
5 Are you ready for some chem Lab???? Polymer Laboratory Exercise Oobleck & Glurch
6 Matter and Its Properties all matter takes up space (has volume) and has mass.mass: a measure of the amount of matter.Objects that have a large amount of matter will have a large mass,and objects with a small amount of matter will have a small mass.Basic Building Blocks of Matterall matter is made up of atoms and/or molecules.atom: the smallest unit of an element that maintains theproperties of that element.element: a pure substance made of only one kind of atom.molecule: a substance that is comprised of two or moreelements that are chemically bonded.compound: a substance that is comprised of two or moredifferent elements that are chemically bonded.
7 Properties and Changes in Matter What is a property? a characteristic that defines an entire group of substances.Extensive property: depend on the amount of matter present.ex: volume, mass, energyIntensive property: do not depend on the amount of matter present.ex: melting point (freezing point), boiling point, density,conductivitySubstances can also be further classified: physical properties and chemical properties.Physical properties: a characteristic that can be observed or measured without changing the identity of the substance.ex: melting point, boiling pointA change in a substance that does not involve a change in the identity of a substance is called a physical change.ex: grinding, cutting, changes of state (melting & boiling)Changes inMatter Video
8 Chemical Properties and Chemical Changes 2. chemical properties: pertains to a substance’s ability to undergo changesthat transform it into different substances.ex: combustibility, rusting, tarnishingchemical change: a change in which one or more substances areconverted into different substances.“chemical reaction”GummiBearRxnREACTANTS PRODUCTS
9 Classification of Matter all matter can be classified as either a pure substance or a mixture.pure substances elements & compoundsmixtures a blend of two or more kinds of matter, each of which retains its own identity and properties.Homogeneous mixtures: uniform in composition.ex: salt water solutionHeterogeneous mixtures: not uniform in composition.ex: muddy waterMixtures can be separated physically.FiltrationDecanting (“pouring off”)Paper chromatographyCentrifugationPure substances differ from mixtures in the following ways:Every sample of a pure substance has exactly the same characteristic properties.Every sample of a given pure substance has exactly the samecomposition.SeparatingMixtureSeparatingInk
10 ELEMENTSIntroduction to the Periodic Tablethe elements are organized based on similar chemical properties.vertical columns of the periodic table are called groups.horizontal rows of elements are called periods.Types of ElementsMetals: have luster (shiny) and are good conductorsof heat and electricity.Most metals are solids at room temp.Metals are malleable: they are capable of beinghammered or rolled into thin sheets.Metals are ductile: they can be drawn into a finewire. (due to the high tensile strength of metals)
11 2. Nonmetals: elements that are poor conductors of heat and electricity. many nonmetals are gases at room temperature (some are solids).solid nonmetals are brittle.rarely have metallic luster (dull appearance).usually do not react with acids.3. Metalloids: elements that have some characteristics of metals and some characteristics of nonmetals.
12 According to Element Type The Periodic TableAccording to Element Type