1-1 chem 100, fall 2011 la tech instructor: dr. upali siriwardane e-mail: [email protected]...
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1-1CHEM 100, Fall 2011 LA TECH
Instructor: Dr. Upali Siriwardane
e-mail: [email protected]
Office: CTH 311 Phone 257-4941
Office Hours: M,W, 8:00-9:00 & 11:00-12:00 a.m Tu,Th,F 9:00 - 10:00 a.m.
Test Dates: March 25, April 26, and May 18; Comprehensive Fina
Exam: 9:30-10:45 am, CTH 328.
Chemistry 100(02) Fall 2011
October 3, 2011 (Test 1): Chapter 1 & 2
October 26, 2011 (Test 3): Chapter 3 & 4
November 16, 2011 (Chapter 5 & 6)
November 17, 2011 (Make-up test) comprehensive: Chapters 1-6
9:30-10:45:15 AM, CTH 328
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REQUIRED :
Chemistry: The Molecular Science 4th Edition, John W. Moore, Conrad
L. Stanitski and Peter C. Jurs. 2010 Brooks and Cole ISBN-10:
1439049300 ISBN-13: 9781439049303
OWL: Students are required to buy access to OWL program offered by
Brooks/Cole's)
OPTIONAL :
Study Guide: 4th Edition, John W. Moore, Conrad L. Stanitski and Peter C. Jurs.
2010 Brooks and Cole Edited by Michael J. Sanger.
Student Solutions Manual: The Molecular Science, 4th by Moore/Stanitski/Jurs,
Edited by Jusy L. Ozment
Text Book & Resources
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Chapter 1. 1. Why Care about Chemistry
2. Molecular Medicine
3. How Science is Done
4. Identifying Matter: Physical Properties
5. Chemical Changes and Chemical Properties
6. Classifying Matter: Substances and Mixtures
7. Classifying Matter: Elements and Compounds
8. Nanoscale Theories and Models
9. The Atomic Theory
10. The Chemical Elements
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Chapter 1. KEY CONCEPTS What is chemistry?
Scientific Method. Scientific Measurement Physical changes and properties. Temperature Conversions. Factor label method. Conversion factors. Density Calculations. Chemical change and properties. Categories of matter. Separating Mixtures. Elements and Compounds Atomic symbols
Macro, micro and nano-scales Prefixes of unit of length Properties of the three states of matterKinetic-molecular theory Dalton's atomic theory Three chemical LawsDiscovery of elementsChemical Elements and propertiesChemical SymbolismInterpreting chemical formulas and chemical reaction.
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What is chemistry?Chemistry deals with non-reversible
changes of matter.
Chemistry explains using atoms and molecules.
Chemical Concepts and Models improve your problem solving skills
Chemistry is a Central Science
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Kinetic Molecular Theory
Matter consists of particles (atoms or molecules) in continuous, random motion.
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•can be compressed
•exert pressure on whatever surrounds them
•expand into whatever volume is available
•easily diffuse into one another
•can be described in terms of their temperatures and pressure, the volume occupied,
and the amount (number of molecules or moles) present
Properties of Gases
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Gas Laws (This is not theory)
•Boyle's Law (V and P) •Charles Law (V and T)•Gay-Lussac's combined Gas Law • (V, P and T)•Avogadro's Law (V and n)
•Ideal Gas Law (V, P, n, R and T)
Scientific law is a summary or pattern
in observation
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Kinetic Molecular Theory: Gases
particles in continuous, random, rapid motion
collisions between particles are elastic
volume occupied by the particles is negligibly small effect on their behavior
attractive forces between particles have a negligible effect on their behavior
gases have no fixed volume or shape, take the volume and shape of the container
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Kinetic Molecular Theory: Solidparticles are tightly packed together in regular array
particles vibrate about average positions
seldom squeeze past other atoms
results in a rigid material with a small, fixed volume for a given mass
external shape often reflects internal arrangement of particles
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Kinetic Molecular Theory: Liquid
particles are arranged more randomly than in solid
particles less confined so that they can move past one another
particles are a little further apart, thus slightly larger, fixed volume
particles are constantly interacting with one another
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Alchemist: Discovery of Elements
Early scientist observed chemical changes of matter. They called these changes chemical reactions when there are changes in substances or the physical & chemical properties of the matter. They also observed a pattern or a repeatable observation during chemical reactions.
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•Law of Conservation of Mass:
•Law of Constant Proportions:
•Law of Multiple Proportions:
Three Observed Chemical Laws:
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Law of Conservation of Mass
Total mass after a chemical reaction is same as before the reaction.
H2 + 1/2 O2 ---> H2OHydrogen (4g) + oxygen (32g) ----> water 36g after
the reaction.
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•A given chemical compound always contains exactly the same proportion of elements by
weight.
• 36g of water contains
• 4g of hydrogen and 32g of oxygen
•take any other chemical compound.
Law of Constant (Definite) Proportions
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When two elements make a series of chemical compounds, the ratio of the masses of the second
elements that combine with 1 gram of the first element can always be reduced to simple whole
numbers.
C O
E.g. carbon monoxide 1g 1.33g
carbon dioxide 1g 2.66g
Law of Multiple Proportions
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Dalton’s atomic theoryAll matter is composed of atoms -- the smallest
particle of an element that takes part in a chemical reaction.
All atoms of an element are alike.
Compounds are combinations of atoms of one or more elements. The relative number of atoms each element is always the same.
Atoms cannot be created or destroyed by a chemical reaction. They only change how they combine with each other.
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What is an Atom?
Very small particle.Smallest particles of elements and molecules
There about 110 types of elements or Atoms.
Different atoms have different physical properties and chemical reactivity
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Models of matter
Models are commonly used to help visualize atoms and molecules.
Atom - The smallest unit of an element that has all of the properties of an element.
Molecule -The smallest unit of a pure substance that has the properties of that substance. It may contain more that one atom and more than one element.
Ions - Charged particles formed by the transfer of electrons between atoms or molecules
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Properties of SubstancesPhysical properties:
Physical properties are descriptions of matter such as color, density, viscosity, boiling point, and melting point.
Chemical properties:
Chemical properties relates to the changes of substances making up the matter. For example, corrosiveness, Flammability
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one that can be observed without changing the substances present in the sample
Examples
– color density– odor melting point– taste boiling point– feel compressibility
Properties of Matter: Physical Properties
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Properties of MatterChemical Property
the tendency to react and form new substances
reactants undergo chemical change to produce products: Chemical Reaction
sucrose => carbon + water
reactant products
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Extensive and Intensive Properties
Extensive properties
Depend on the quantity of sample measured.
Example - mass and volume of a sample.
Intensive properties
Independent of the sample size.
Properties that are often characteristic of the substance being measured.
Examples - density, melting and boiling points.
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Chemical verses Physical change
Sodium reacting Iodine changing
with chlorine. from a solid to a gas
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Pure substances
Element• Cannot be converted to a simpler form by a chemical
reaction.• Example hydrogen and oxygen
Compound• Combination of two or more elements in a definite,
reproducible way.
• Example water - H2O
Both elements and compounds have characteristic properties such as color, boiling point and reactivity
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Allotropes
GraphiteDiamond
Buckminsterfullerine
Forms of element that has different bonding pattern
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Mixtures Mixtures
HeterogeneousHeterogeneous HomogenousHomogenous
CompoundsCompounds
AtomsAtoms
ElectronsElectrons
NucleusNucleus
ProtonsProtonsNeutronsNeutrons
Pure SubstancesPure Substances
ElementsElements
Hierarchy of Matter
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Mixtures• A combination of two or more pure
substances.
• Homogeneous - Uniform composition (solution)
• Heterogeneous - Non-uniform composition
Which are homogeneous or heterogeneous?
• Blood Urine “T-Bone” steak
• Gasoline Twinkie Salad Dressing
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Types of Elementsmetals
nonmetals
metalloids – semimetals
Artificial Elements
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Atomic SymbolsEach element is assigned a unique symbol.
arsenic As potassium Kbarium Ba nickel Nicarbon C nitrogen Nchlorine Cl oxygen Ohydrogen H radon Rnhelium He titanium Tigold Au uranium U
Each symbol consists of 1 or 2 letters. The first is capitalized and the second is lower case.
Symbol may not match the name - often had a different name to start with.
Some elements (about 11) the names were not in English. E.g., Sodium-Na (natrium-latin), potassium-K(kalium-latin).
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Areas of Chemistry“The study of matter and the changes it undergoes.”
Major divisions
Inorganic Compounds of elements other than carbon
Organic Compounds of carbon
Biochemistry Compounds of living matter
Physical Theory and concepts
Analytical Methods of analysis
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How do you Separate Mixtures?
Flotation: based on density
Filtration: Solid- liquid
Distillation- Liquid-liquid
Magnetic Separation- Magnetic
Chromatography:1) Paper 2) Column 3) Gas
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Separate a solid (precipitate) form suspension:_________________
separate solids by differences in melting points:_________________
separate materials based on their differences in absorption on a support:______________
Separation of Mixtures (continued.)
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Chromatography
Liquid-column
Paper
thin-layer (TL Chromatography-TLC)
Gas
HPLC (high pressure liquid chromatogarphy)
Electrophoresis (DNA mapping)
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Physical States
Solid• fixed volume and shape
Liquid• fixed volume• shape of container, horizontal top
surface
Gas• takes shape and volume of container