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Welcome to CHEMISTRY !!!

Welcome to CHEMISTRY !!!. An Observational Science An Experimental Science A Laboratory Science An Interesting Science An Important Science A “Hard” Science. What Happened To The Balloon?. It was Whimpy and Broke! It was fearful of all of the people! Zoller scared it!

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Welcome to CHEMISTRY !!!

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  1. Welcome to CHEMISTRY !!! • An Observational Science • An Experimental Science • A Laboratory Science • An Interesting Science • An Important Science • A “Hard” Science

  2. What Happened To The Balloon? • It was Whimpy and Broke! • It was fearful of all of the people! • Zoller scared it! • It got zapped by Klingons! • Hydrogen burns!

  3. 2H2 (g) + O2 (g) = 2 H2O (g) + Energy • Hydrogen and oxygen are diatomic gases! • Water can be a gas! • ENERGY was given off!-- This is characteristic of an Exothermic Reaction! • This is a balanced chemical reaction!

  4. CHEMISTRY The Study of Matter and its Properties, the Changes that Matter Undergoes, and the Energy Associated with those Changes

  5. Chemistry as the Central Science Atmospheric Sciences Physics Oceanography Medicine Economics Governments Chemistry People Geology Biology Politics Astronomy Anthropology

  6. Chemistry Homework !!! “ Chemistry is not a spectator sport, you must become involved, and that means that you must do homework!” Linus Pauling - 1967

  7. Student versus Class Computer Notes Student notes will have answers missing, and you will have to fill Them in during or before class! Class notes will have the answers in them, so you can copy them down and have the answers. This requires you, the student to do some writing during class in addition to the materials that I write on the overheads. The reason for this is that you will remember better by using more of your senses during class time. Calculate the volume of a cube with sides of 2.0 inches? Student: 2.0 in x 2.0 in x 2.0 in = Class notes: 2.0 in x 2.0 in x 2.0 in = 8.0 in3 Suggestion : You do the work before class, and in that way learn what is going to be done in class, then check in class!

  8. Chemistry 142 Text: Chemical Principles Fifth Edition - By Steven S. Zumdahl Chapter #1 :Chemists and Chemistry Chapter #2 : Atoms, Molecules, and Ions Chapter #3 : Stoichiometry: Mole - Mass Relationships in Chemical Systems Chapter #21: The Nucleus: A Chemist’s View Chapter #4 : Types of Chemical Reactions and Solution Stoichiometry Chapter #5 : Gases Chapter #6 : Chemical Equilibrium Chapter #7 : Acids and Bases Chapter #8 : Applications of Aqueous Eqilibria

  9. Chapter# 1 : Chemists and Chemistry 1.1 Thinking Like a Chemist 1.2 A Real-World Chemistry Problem Stephanie Burns: Chemist, Executive 1.3 The Scientific Model Critical Units! 1.4 Industrial Chemistry 1.5 Polyvinyl Chloride (PVC): Real-World Chemistry

  10. Chemical technicians check water quality.

  11. Figure 1.1: Chemists interact

  12. Chemists at work Source: Photo Researchers

  13. Acid-damaged paper Source: Fundamental Photos

  14. Figure 1.2 Paper: A Polymer called Cellulose The Polymer cellulose, which consists of B-D-glucose monomers

  15. Figure 1.3: Schematic diagram of the strategy for solving the problem of the acid decomposition of paper.

  16. Artist's conception of the lost Mars Climate Orbiter. Source: NASA

  17. Figure 1.4: The various parts of the scientific method

  18. Industrial processes require large plants for production of chemicals. Source: Photo Researchers

  19. HH CC Poly(Vinyl Chloride) (PVC) and Teflon HHHHHHHH CCCCCCCC n HCl HCl HCl HClHCl Vinyl chloride PVC FF FFFFFFFF CC CCCCCCCC n FF FFFFFFFF Teflon Tetrafluoroethylene

  20. Scientist inspecting Source: Corbis

  21. Table 1.1 (P 12) Types of Additives Commonly Used in the Production of PVC Type of Additive Effect Plasticizer Softens the Material Heat stabilizer Increases resistance to thermal decomposition Ultraviolet absorber Prevents damage by sunlight Flame retardant Lowers flammability Biocide Prevents bacterial or fungal attack

  22. Definitions-I Matter- The “stuff” of the universe: books, planets, trees, professors - anything that has mass and volume. Composition - The types and amounts of simpler substances that make up a sample of matter. Properties - The characteristics that give each substance a unique identity. Physical Properties - are those the substance shows by itself, without interacting with another substance ( color, melting point, boiling point,density, etc.) Chemical Properties - are those that the substance shows as it interacts with, or transforms into, other substances (flammability, corrosiveness, etc.)

  23. STATES OF MATTER -and The World around US • SOLID - The Earth • LIQUID - Water • GAS - The Atmosphere

  24. Energy Involved in Phase Changes Liberates Energy Gas Boiling Condensation Liquid Melting Freezing Solid Requires Energy

  25. Definitions - II Energy - The capacity to do work! Potential Energy - The energy due to the position of the object.Or Energy from a chemical reaction. Kinetic Energy - The energy due to the motion of the object.

  26. Units Used in Calculations Length : A car is 12 feet long, not “12” ! A person is 6 feet tall, not “6” ! Area : A carpet measuring 3 feet(ft) by 4 ft has an area of: ( 3 x 4 )( ft x ft ) = _________ ft2 Speed and Distance : A car traveling 350 miles(mi) in 7 hours(hr) has a speed of: 350 mi / 7 hr = 50 mi / hr In 3 hours the car travels: 3 hr x 50 mi / hr = ___________ mi

  27. Derived SI Units Quantity Definition of Quantity SI unit Area Length squared m2 Volume Length cubed m3 Density Mass per unit volume kg/m3 Speed Distance traveled per unit time m/s Acceleration Speed changed per unit time m/s2 Force Mass times acceleration of object kg * m/s2 ( =newton, N) Pressure Force per unit area kg/(m2) ( = pascal, Pa) Energy Force times distance traveled kg * m2/s2 ( = joule, J)

  28. How to Solve Chemistry Problems 1) Problem: States all of the information needed to solve the Problem. 2) Plan: Clarify the known and unknown. Suggest the steps needed to find the solution. Develop a “roadmap”solution. 3)Solution: Calculations appear in the same order as outlined. 4) Check: Is the result what you expect or at least in the same order of magnitude! 5) Comment:Additional information as needed.

  29. Conversion Factors : Unity Factors - I Equivalent factors can be turned into conversion factors by dividing one side into the other! 1 mile = 5280 ft or1 = 1 mile / 5280 ft = 5280 ft / 1 mi 1 in = 2.54 cm or1 = 1 in / 2.54 cm = 2.54 cm / 1 in In converting one set of units for another, the one desired is on top in the conversion factor, and the “old” one is canceled out! convert 29,141 ft into miles! 29,141 ft x 1 mi / 5280 ft = ______________ mi

  30. Conversion Factors - II 1.61 km = 1 mi or 1 = 1.61 km / 1 mi Convert 5.519 miles in to kilometers 5.519 mi x 1.61 km / mi = 8.89 km conversions in the metric system are easy, as 1 km = 1000 m and 1 meter (m) = 100 centimeters(cm) and 1 cm = 10 millimeters(mm) Therefore: into cm and mm! 8.89 km x 1000m / 1 km = 8,890 m 8,890 m x 100 cm / m = 889,000 cm

  31. 3.56 lbs 1 kg 1000g 1000mg 1 hr 1 min hr 2.205 lbs 1 kg 1 g 60 min 60 sec x x x x x = = ____ mg/ sec Conversion Factors - III • Multiple conversion factors! • Convert 3.56 lbs/hr into units of milligrams/sec.

  32. Conversion Factors - IVmetric volume to metric volume • 1.35 x 109 km3 = volume of world’s oceans • 1.35 x 109 km3 x (103 m/1 km )3 x ( 103 l/m3) = 1.35 x 1021 liters • conversion factors: 1000m = 1km 1000 l = 1m3

  33. Conversion Factors - V Calculate the mass of 1.00 ft3 of Lead (density=11.4g/ml)? • 1.00 ft3 x (12 in/ft)3 x (2.54 cm/in)3 = 28,316.84659 cm3 • 2.83 x 104 cm3 x 11.4 g/cm3 = 322,620.0000 g • Ans. = 3.23 x 105 g = ________________ kg

  34. An Example Problem! The Volume of an irregularly shaped solid can be determined from the volume of water it displaces. A graduated cylinder contains 245.0 ml water. When a small piece of Pyrite, an ore of Iron, is submerged in the water, the volume increases to 315.8 ml. What is the volume of the piece of Pyrite in cm3 and in liters. Vol (ml) = 315.8 ml - 245.0 ml = 70.80 ml Vol (cm3) = 70.80 ml x 1 cm3/ 1 ml = 70.80 cm3 Vol (liters) = 70.80 ml x 10 -3liters / ml = __________liters

  35. Archimedes Principle Problem Problem: Calculate the density of an irregularly shaped metal object that has a mass of 567.85 g if when it is placed into a 2.00 liter graduated cylinder containing 900.00 ml of water, the final volume of the water in the cylinder is 1,277.56 ml? Plan: Calculate the volume from the different volume readings, and calculate the density using the mass that was given. Solution: Volume = 1,277.56 ml - 900.00 ml = 377.56 ml mass 567.85 g Density = = = _________ g / ml volume 377.56 ml

  36. Definitions - Mass & Weight Mass - The quantity of matter an object contains kilogram - ( kg ) - the SI base unit of mass, is a platinum - iridium cylinder kept in Paris as a standard! Weight - depends upon an object’s mass and the strength of the gravitational field pulling on it.

  37. A Sample Problem - I Length (km) of Fiber Length (m) of Fiber Mass (lb) of Fiber Mass (lb) of Cable International computer communications will soon be carried by optical fibers in cables laid along the ocean floor. If one strand of optical fiber weighs 1.19 x 10 -3 lbs/m, what is the total mass (in kg) of a cable made of six strands of optical fiber, each long enough to link New York and Paris? (8.85 x 103 km). Mass (kg) of Cable 1 km = 103 m 2.205 lb = 1 kg 1m = 1.19 x 10 -3 lb 6 fibers = 1 cable

  38. Sample Problem - II Length (m) of Fiber = 8.85 x 103 km x 103m / km = 8.85 x 106 m Mass (lb) of Fiber = 8.85 x 106 m x 1.19 x 10-3 lb / 1m = 1.05 x 104 lb Mass (lb) of cable = 1.05 x 104 lb / 1 fiber x 6 fibers / 1 cable = 6.30 x 104 lb / cable Mass (kg) of cable = 6.30 x 104 lb / 1 cable x 1kg / 2.205 lb = 2.86 x 104 kg / cable

  39. A Problem on Density - I Lengths (mm) of sides Mass (mg) of Li Lengths (cm) of sides Mass (g) of Li Volume (cm3) Density (g/cm3) of Li Lithium (Li) is a soft, gray solid that has the lowest density of any metal. If a slab of Li weighs 1.49 x 103mg and has sides that measure 20.9 mm by 11.1 mm by 12.0 mm, what is the density of Li in g/ cm3 ?

  40. Density Problem - II 1 g Mass (g) of Li = 1.49 x 103 mg x = 1.49 g Length (cm) of one side = 20.9 mm x 1cm / 10 mm = 2.09 cm Similarly, the other side lengths are 1.11 cm and 1.20 cm Volume (cm3) = 2.09 cm x 1.11 cm x 1.20 cm = 2.78 cm3 Density of Li = = ___________ g/cm3 103 mg 1.49 g 2.78 cm3

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