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Feb 10
• Warm up – grab a packet from the black cart
And
• Warm up - Get your lab notebook set it up for a demo
If you did not take the test or finish the test yesterday see me
Demo # 2 Kinetic Theory
• Introduction to unit 3
• Title = kinetic theory demo
• Question – is the kinetic theory of matter true??
Demo – Kinetic theory
• Main idea – all matter is made up of particles and these particles are always moving to some extent
• Crushing this can without using my hands is an example of this
Unit 3: Properties and States of Matter
Kinetic Theory
• The kinetic theory explains how particles move in different states of matter.
– All matter is composed of small particles (molecules, atoms, and ions).
– The particles are in constant, random motion.– The amount of motion is proportional to the
temperature. Increased temperature means increased motion.
– Solids, liquids and gases differ in the freedom of motion of their particles and the extent to which the particles interact.
Three states of matter
SOLID LIQUID GAS
•Definite Shape
•Definite Volume
•Cannot be compressed
•Cannot flow
•Definite Volume
•Can flow
•No definite Shape
•Cannot be compressed
•No definite Volume
•No definite Shape
•Can flow
•Can be compressed
Plasma
• The new fourth state of matter
• When any matter becomes tooo hot the electrons are stripped / fall off
• This matter shares properties of a gas and a liquid
• Examples - sun
Plasma TV
• Different type of plasma
• Here we have a gas that the electrons are just loose- not bound to any nucleus
• lightning
Kinetic Theory
• Motion in a gasThe constant motion of particles
in a gas allows a gas to fill any container
• Three Main points1. Particles of a gas are in constant, random motion2. The motion of one particle is unaffected by another
unless they collide3. The Forces of attraction among particles can be ignored
• POSITIVE AND NEGATIVE CHARGES
Ex) air freshener
Kinetic Theory
• Motion in a liquid– Particles in a liquid are more closely packed
than particles in a solid• Attractive forces apply
– A Liquid can take the shape of a container because the particles of a liquid can flow to new locations
• The Volume of a liquid is constant because of the attractive forces between particles keep them together
Kinetic Theory
• Motion in a solid– Solids have a definite shape and volume
because particles are in a solid vibrate in a fixed location
ex) People sitting in a theatre or a classroom
Warm-Up – get you lab notebook
• Put this in your lab notebook
• What state of matter has…– 1. Definite shape, definite volume– 2. No definite shape, no definite volume– 3. Definite volume, no definite shape
– Choices – solid, liquid , and gases
Schedule
• Warm up-fast fact
• Phase Changes
• Kinetic theory lab
• Phase change handout – in you packet from yesterday
Fast Fact - What is the origins of Valentines day
• 290 AD – Rome declared the soldiers could not be married
• Secretly went to Bishop Valentine to get married
• Became a saint and his day is Feb 14th
Kinetic theory lab – put this in lab note book
Title – kinetic theory lab
Problem – we need to understand what is a phase change
Data- leave space for a data table
Conclusion – “ answer questions from lab ”
Kinetic Theory Lab
• Remember– Every minute take a reading from the thermometer
– Once the beaker is on the hot plate DO NOT TOUCH IT
– Mark , highlight when the ice has completely turned into water, and when water begins to boil
– Continue to take data until the water has completely boiled for 5 minutes
ExampleData Table in notebook
time (min) temperature (C)
0 1
1 5
2 11
3 12
4 13
5 14
6 15
7 15
After your done with the water
• Build your graph
• Answer the conclusion questions
Honors
• You must write a formal lab on this experiment
Thermal Energy
• Thermal energy is heat. It can also be defined as the sum of the kinetic energy of the particles in a substance. Has to do with temperature and mass.
– Temperature is a measurement of the average kinetic energy of a substance.
• Increases kinetic energy (speed of particles)• Higher Temperature = molecules moving faster
– Solid < Liquid < Gas
Phase Change
• Definition – the reversible physical change that occurs when a substance changes from one state of mater into another
• The temperature does not change during a phase change
• Energy is either stored or released during a phase change
Common Phase changes
• 1. Melting solid -> liquid• 2. Freezing liquid -> solid• 3. Vaporization liquid -> gas , endothermic
• 4. Evaporation liquid -> gas , below boiling point
• 5. Condensation gas - > liquid, cloudy bathroom mirror
• 6. Sublimation solid - > gas, dry ice
• 7. Deposition Gas -> solid, Frost on a window
Freezing / Melting point
• Freezing point– Temperature in which a liquid becomes a
solid• Molecules become more closely packed together• Water – below 0 degrees C
• Melting Point – temperature in which a solid become a liquid– Every solid has a different MP
• Water – Above 0 Celsius• Mercury - -32 C
Boiling Point / Condensation
• Boiling point – Temperature where a liquid becomes a gas
• Water 90-100 degrees C
Surface area – part of water that is exposed
Larger surface area – faster reaction
• Condensation– A Gas cools to become a liquid– Water on a mirror after a shower
Sublimation
• Were a solid changes into a gas
• Dry ice
• Endothermic reaction – need energy
• Dry ice absorbed the heat energy from its environment and transformed straight into a gas
After Lab
• Vocab – now its late
• Phase change handout
• Was in back of packet
• Atomic Model Project is due Monday
Liquid Nitrogen
• Beaker: What is the boiling point?
• Balloons: Do you see the three phases?
• Apples and Bananas: Solids are Brittle
• Placed in a bottle: Can Anyone Explain?
Composition of Matter
Matter
• Anything that has mass and takes up space
• pure substance or mixture
Pure Substance
• A pure substance can not be broken down physically into anything else. –Element–Compound
Element
• Element – on periodic table
• Elements are composed of only one type of atom
• Has one capital letter– Na– Cl– F
• Atom – smallest particle of an element
Compound or Molecule
• Compound – combo of 2 or more elements
• Two or more capital letters– NaCl– H2O– MgO2
– CO2
• Molecule – smallest part of a compound
Pure Substances
• Compound
– properties differ from those of individual elements
– EX: table salt (NaCl)
Pure Substances
• For example…
Two different compounds, each has a definite composition.
Inorganic vs. Organic Compounds
• Inorganic compounds have no Carbon– NaCl, H2O, NH4
• Organic compounds have carbon– C6H12O6 C2H6
Biological Organic Compounds
• Proteins – egg, meat
• Carbohydrates – bread, sugar, pasta
• Lipids – lard, butter, oil
Quick Quiz
On A separate piece of paper answer the following question using your notes
1. What is the difference between the melting phase and the freezing phase?
2. List the qualification of a liquid?3. Write an example of a substance in each phase of
matter?4. What is the difference between an Element and a
compound?5. What is the difference between a organic and inorganic
compound?
Mixtures
• two or more substances that can be physically separated
Heterogeneous Mixtures
• Heterogeneous mixture: See component parts
• Examples
–Granite
–Concrete
–Dry Soup Mix
Homogeneous Mixtures
• Homogeneous mixture: cannot see component parts
• Examples:
–Kool Aid
–Sweet Tea
Mixtures can be…
• Gas in Gas (air) – what we breath
• Gas in Liquid (soda) the carbonation
• Liquid in Liquid (mixed fruit juices)
• Liquid in Solid (Iced Tea) – energy needs to be implied
• Solid in Solid (Concrete, Alloys)
A “microscopic” view
Classifying Matter
1. Classify the following as an element, compound, or mixture (heterogeneous or homogeneous).
• _____ air _____ oxygen• _____ tin can _____ sugar• _____ Windex _____ Salad dressing• _____ sand and sugar _____ gummi bear
2. A white solid is dissolved in water. The resulting colorless, clear liquid is boiled in a beaker until dryness. White crystals remain in the beaker. The liquid can be classified as a(n) ______________.
HO E
E OC
HO HE
HE HO
Homogeneous mixture
-Which box represents an element, a compound and a mixture?
Quiz
Complete Identification and Separation Lab
• Example– Saltwater
Composition
Homo mixture
Type of Mixture
Solid/liquid
Identify each of the items as an element, an inorganic compound, an organicCompound, a homogeneous mixture, or a heterogeneous mixture. If it is a Mixture, tell the type (gas/gas, gas/liquid, etc)
Review Lab
Mixtures can be separated by…
• Dissolving
• Filtering
• Evaporating
• Magnetic Separation
• Chromatography
Unit 6 Quiz
Warm Up
• Please place your formal lab report on the front table.
• What type of substance can be separated using physical means such as evaporating, distilling, filtering, chromatography, or magnetic separation?
– Answer choices: elements, compounds, or mixtures
Review Quiz
• More Practice Identifying Matter
Physical/Chemical Properties Lab
• Label the top of the next full page in your composition notebook with the title above and today’s date (2/21/2008).
• Write the definition for Physical and Chemical properties.
– Physical Properties: Any characteristic of a material that you can observe directly or measure with a tool without changing the composition of the substance. (It does not change chemically)
– Chemical Properties: Any characteristic of a material that indicates whether it can undergo change that will alter the composition of the substance. (It does change chemically)
Make a table like this in your composition notebook to record
your data
Physical/Chemical Properties Lab
• You and your lab partner must go around to each station and identify whether the property being demonstrated is a physical or chemical property and state why.
• boiling point, combustion, freezing/melting point, density, oxidation, solubility, viscosity, conductivity, corrosion, acid or base
These are the properties you have to choose from
Warm-Up
• Please make a list of physical and chemical properties:
Physical Properties (7) Chemical Properties (3)
Boiling pointMelting/freezing pointSolubilityConductivityDensityViscosityAcid or base
OxidationCorrosionCombustion
Physical Property
• Any characteristic of a material that you can observe directly or measure with a tool without changing the composition of the substance. (It does not change chemically)
• Examples: boiling point, freezing/melting point, density, solubility, viscosity, electrical conductivity.
Viscosity
• A fluid’s resistance to flow– High viscosity fluids take longer to pour.– Viscosity may change with temperature.
• Viscosity Demo
Conductivity
• Ability to transmit electrons (electricity)– Conductors vs. insulators
• Metals – good conductors• Non metals – insulators• Some solutions are good conductors that contain
dissolved ions (electrolytes).
Solubility
• Ability to dissolve or be dissolved
• Solubility increased by:
1. Temperature
2. Surface Area
3. Stirring
Density
• Density – the amount of mass of an object related to its volume
• Density = mass (Kg) / volume (cm3)
Complete Density Lab
• When finished let me see your data.
• Once I check your data:
• Work on the density problems on the last page of your packet.
• HW: Density Drill (In your packet) front side only
Review Density Lab
Density Problems
• HW: Lab Report and Density Sheet due tomorrow
Warm-Up
• What is the density of a piece of wood that has a mass of 24.0 grams and a volume of 12.0 cm3?
– What would the density be if the piece of wood were cut in half?
• A piece of wood that measures 3.0 cm by 6.0 cm by 4.0 cm has a mass of 36.0 grams. What is the density of the wood? Would the piece of wood float in water? (volume = L x W x H)
• The volume of a solution went from 40 ml to what you see above in a graduated cylinder after putting in a gold ring. If the mass of the gold ring is measured to be 30 grams, what is the density of the gold ring?
Review Density Lab
1 cm3 = 1mL = 1 g
Acids and Bases• Acids
– Form hydrogen (H+) ions in solution
– Low pH ( < 7 )– Sour/tart taste– electrolytes– React with metals to
form H2 gas– Corrosive – tissue
damage/burns – Change color of
indicators– React with bases to
form salt & water
• Bases– Form hydroxide (OH-) ions
in solution– High pH ( > 7 )– Bitter taste– electrolytes– Feel slippery– Often crystalline solids
when undissolved– Corrosive – burns– Change color of indicators– React with acids to form
salt & water
pH
• pH is a measure of the concentration of H+ ions in solution (0-14)– Acids < 7– Neutral = 7– Bases > 7
• pH meter uses electrodes to read electrical conductivity in solution
• pH paper changes color when exposed to acids/bases– match pH paper color to a chart to get pH– Follows ROYGBIV A-B
Litmus
• Litmus paper is another common indicator– Acids turn it red – Bases turn it blue
Common Examples
• Acids– Citric– Lactic– Acetic (vinegar)– Carbonic (carbonated
drinks)– Hydrochloric (HCl –
stomach acid)– Sulfuric, Nitric,
Phosphoric (fertilizers)
• Bases– Ammonia– Clorox– Magnesium Hydroxide
(antacid)– Sodium hydroxide
(soap, oven/drain cleaners)
– Aluminum Hydroxide (antacid, water purification, color-fast fabrics)
LAB: Acids and Bases
Warm Up
• Get started on Acid-Base WS from your packet.– Omit #’s 7, 13, 15 on front and compound B
on the back
Neutralization
• Acids and Bases neutralize each other– Acid + Base Salt + Water
• HCl + NaOH H2O + NaCl
Chemical Property
• Characteristic of a material that indicates whether it can undergo change that will alter the composition of the substance. (It does change chemically)
• Examples: Oxidation, Corrosion, Combustion
Oxidation
• Ability to bind with oxygen during a reaction– Iron rusting
• Iron + Oxygen Iron oxide
2 Fe + O2 2 FeO
Combustibility
• Ability to burn– Cremora Demo
Corrosion
• Ability to break down a metal– Silver Tarnishing
• Silver + Sulfur Silver Sulfide
Ag + S AgS
Decomposition
React/Not react with acids
Warm Up
• Get out practice test and get ready for review.