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Unit 1. Matter and Change. Do Now:. What are the S tate of Matter?. Objectives : Define the term “chemistry” Describe the difference branches of Chemistry. Describe the difference between a physical change and a chemical change and give several examples of each.
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Do Now: • What are the State of Matter?
Objectives: • Define the term “chemistry” • Describe the difference branches of Chemistry. • Describe the difference between a physical change and a chemical change and give several examples of each. • Describe different characteristics of the three states matter. • Classify a mixture as homogeneous or heterogeneous. • Classify a pure substance as an element or a compound.
Chapter 1 Section 1 Chemistry is a Physical Science
Chemistry is the study of matter and the changes that it undergoes. Biological Science Physical Sciences Chemistry Chemistry is central to all sciences. Both living and non living matter have a chemical structure.
Chemistry deals with: What is material made of? What is the makeup and internal arrangement of the atoms? How does it behave when heated, cooled or mixed with other materials?
Branches of Chemistry Organic chemistry – the study of carbon containing compounds. Inorganic chemistry – the study of substances that do not contain carbon (metals and gases). Physical chemistry – the study of the properties and changes of matter and their relation to energy.
Analytical chemistry –the identification of the components and composition of materials. Biochemistry – the study of the processes occurring in living systems.
Types of Research • Basic Research - carried out for the sake of increasing knowledge. • Most basic research is carried out in universities. • Research is normally published in scientific journals.
Types of Research • Applied Research - carried out to solve a problem. • Research is carried out by companies to make a profit. • Usually short term goals set by the company.
Summary • Define the word chemistry. • Name the five branches of chemistry. • Define basic and applied research.
States of Matter • There are Four state of matter • A. Solid • B. Liquid • C. Gas • D. Plasma • State of matter depends on Kinetic Energy between the particles
A. Kinetic Molecular Theory • KMT • Particles of matter are always in motion. • The kinetic energy (speed) of these particles increases as temperature increases.
Four States of Matter • A. Solids • very low KE - particles vibrate but can’t move around • fixed shape • fixed volume
Four States of Matter • B. Liquids • low KE - particles can move around but are still close together • variable shape • fixed volume
Four States of Matter • C. Gases • high KE - particles can separate and move throughout container • variable shape • variable volume
Matter and its Properties • It’s Classified!
Objective • Distinguish between: • intensive and extensive properties • Physical & chemical changes/properties • Classify matter
Properties & Changes in Matter • Extensive vs. Intensive • Physical vs. Chemical
A. Extensive vs. Intensive • Extensive Property • depends on the amount of matter present • ex,.- • Intensive Property • depends on the identity of substance, not the amount • Ex.-
A. Extensive vs. Intensive • Extensive Property • depends on the amount of matter present • ex,.- Volume, mass, Energy • Intensive Property • depends on the identity of substance, not the amount • Ex.- melting point, boiling point, conduct electricity or heat • WHAT ABOUT DENSITY??
A. Extensive vs. Intensive • Examples: • boiling point • volume • mass • density • conductivity
A. Extensive vs. Intensive • Examples: • boiling point…… intensive • Volume …. extensive • Mass ….. extensive • Density ….. intensive • Conductivity ….. intensive
PROPERTYB. Physical vs. Chemical • Physical Property • can be observed without changing the identity of the substance • Chemical Property • describes the ability of a substance to undergo changes in identity
B. Physical vs. Chemical physical chemical physical physical chemical • Examples: • melting point • flammable • density • magnetic • tarnishes in air
B. Physical vs. Chemical physical chemical physical physical chemical • Examples: • melting point • flammable • density • magnetic • tarnishes in air
CHANGEC. Physical vs. Chemical • Physical Change • changes the form of a substance without changing its identity • properties remain the same • Chemical Change • changes the identity of a substance • products have different properties
B. Physical vs. Chemical • Signs of a Chemical Change • change in color or odor • formation of a gas • formation of a precipitate (solid) • change in light or heat
Properties and Changes in Matter In the example of burning of charcoal, carbon and oxygen are the reactants in the combustion reaction. Carbon dioxide is the product. carbon + oxygen carbon dioxide C + O2 CO2 (reactants) (product)
B. Physical vs. Chemical • Examples: • rusting iron • dissolving in water • burning a log • melting ice • grinding spices
B. Physical vs. Chemical chemical physical chemical physical physical • Examples: • rusting iron • dissolving in water • burning a log or charcoal • melting ice • grinding spices
Four States of Matter • D. Plasma • very high KE - particles collide with enough energy to break into charged particles (+/-) • gas-like, variableshape & volume • stars, fluorescentlight bulbs, CRTs
SOLUTIONS AND MIXTURES
Objective: • Classification of Matter • DO NOW: • What is a solution? • Describe the difference between a heterogeneous and homogenous mixture
A. Pure Substances • Element • composed of identical atoms • EX: copper wire, aluminum foil
A. Pure Substances • Compound • composed of 2 or more elements in a fixed ratio • properties differ from those of individual elements • EX: table salt (NaCl)
A. Pure Substances • Law of Definite Composition • A given compound always contains the same, fixed ratio of elements. • Law of Multiple Proportions • Elements can combine in different ratios to form different compounds.
A. Pure Substances • For example… Two different compounds, each has a definite composition.
Pure Substances(constant composition) • Elements • Listed on the Periodic Table • Cannot be broken down into unique components • Na, Cl, Al, O2, S8 • Compounds • Made of elements that are chemically joined • Can be broken down • NaCl, H2O, AlCl3, H2SO4
B. Mixtures • Variable combination of 2 or more pure substances. Heterogeneous Homogeneous
B. Mixtures(variable composition) • Homogeneous – Solutions • evenly distributed • Heterogeneous • not evenly distributed
Tyndall Effect B. Mixtures • Solution • homogeneous • very small particles • no Tyndall effect
B. Mixtures • Colloid • heterogeneous • medium-sized particles • Tyndall effect • particles don’t settle • EX: milk
B. Mixtures • Suspension • heterogeneous • large particles • Tyndall effect • particles settle • EX: fresh-squeezed lemonade
C. Mixtures • Examples: • mayonnaise • muddy water • fog • saltwater • Italian salad dressing
C. Mixtures colloid suspension colloid solution suspension • Examples: • mayonnaise • muddy water • fog • saltwater • Italian salad dressing
MIXTURE PURE SUBSTANCE yes no yes no Is the composition uniform? Can it be chemically decomposed? Colloids Suspensions A. Matter Flowchart MATTER yes no Can it be physically separated? Homogeneous Mixture (solution) Heterogeneous Mixture Compound Element