UNIT 1 BAUGHMAN KINETIC THEORY HEADS UP FOR FRIDAY: QUIZ!!! TEST: 9/9/2015

KINETIC THEORY Kinetic Theory states that the tiny particles in all forms of matter are in constant motion.  Kinetic refers to motion  Helps you understand the behavior of solid, liquid, and gas atoms/molecules as well as the physical properties  Provides a model behavior based off three principals 3 Principles of Kinetic Theory  All matter is made of tiny particles (atoms)  These particles are in constant motion  When particles collide with each other or the container, the collisions are perfectly elastic (no energy is lost)

STATES OF MATTER What is matter?  Anything that has mass & takes up space 5 States of Matter  Solid  Liquid  Gas  Plasma  Bose-Einstein Condensates

SOLIDS Particles are tightly packed and close together Particles do move but not very much Definite shape and definite volume (because particles are packed closely and do not move) Most solids are crystals Crystals are made of unit cells (repeating patterns)  The shape of a crystal reflects the arrangement of the particles within the solid

SOLIDS Unit cells put together make a crystal lattice (skeleton for the crystal) Crystals are classified into seven crystal systems: cubic, tetragonal, orthorhombic, monoclinic, triclinic, hexagonal, rhombohedral Unit cell  crystal lattice  solid

SOLIDS Amorphous Solid:  A solid with no defined shape (not a crystal)  A solid that lacks an ordered internal structure  Examples: Clay, PlayDoh, Rubber, Glass, Plastic, Asphalt Allotropes:  Solids that appear in more than one form  2 or more different molecular forms of the same element in the same physical state (have different properties)  Example: Carbon  Powder = Graphite  Pencil “lead” = graphite  Hard solid = diamond

SOLIDS

SOLIDS Allotropes of Carbon: a) diamond b) Graphite c) lonsdaleite, d)buckminsterfullerene (buckyball) e) C540 f) C70 g) amorphous carbon h) single-walled (buckytube)

LIQUIDS Particles are spread apart Particles move slowly through a container No definite shape but do have a definite volume Flow from one container to another Viscosity – resistance of a liquid to flowing  Honey – high viscosity  Water – low viscosity chemed.chem.purdue.edu/.../graphics

GASES Particles are very far apart Particles move very fast No definite shape and No definite volume

PLASMA Particles are extremely far apart Particles move extremely fast Only exists above 3000 degrees Celsius Basically, plasma is a hot gas When particles collide, they break apart into protons, neutrons, and electrons Occurs naturally on the sun and stars

BOSE-EINSTEIN CONDENSATE Particles extremely close together Particles barely move Only found at extremely cold temperatures Basically Bose-Einstein is a cold solid Lowest energy of the 5 states/phases of matter

GASES AND PRESSURE Gas pressure is the force exerted by a gas per unit surface area of an object  Force and number of collisions  When there are no particles present, no collisions = no pressure = vacuum  Atmospheric Pressure is caused by a mixture of gases (i.e. the air)  Results from gravity holding air molecules downward in/on the Earth’s atmosphere; atmospheric pressure decreases with altitude, increases with depth  Barometers are devices used to measure atmospheric pressure (contains mercury)  Standard Pressure is average normal pressure at sea level  As you go ABOVE sea level, pressure is less  As you go BELOW sea level, pressure is greater

GASES AND PRESSURE STP  Standard Temperature and Pressure  Standard Pressure 1 atm (atmosphere), also kPa (kilopascal)  Standard Temperature is 0°C or 273 K  If given in Fahrenheit, you must convert first!  °F = (9/5)°C + 32  °C = (5(°F-32)) / 9 Remember order of operation rules  K = °C  °C = K – 273

What questions have we answered? Using complete sentences, answer each of the following essential questions in your notebook. (You do NOT need to rewrite the question, but I should be able to tell what the question was by your answer.) 1.What is the kinetic theory of matter? 2.What are the characteristics of matter? 3.What are the 3 types of matter found extensively on Earth? 4.How do particles move in the different states of matter?

Friday 8/29 Standards of Measurement (p.19-25) Unit (name) Unit (symbol) What does it measure? If units measure the same thing, what makes each unique? Keep adding rows as needed… You WILL have more than this! 1.After quiz- Turn in ‘test’ & scantron (face-down) on front desk. There will be NO TALKING/PHONES until EVERYONE is done with the quiz! 2.Get a textbook 3.Using p.19-25, create a table like the one below with the data you find there. 4.Below your table, define the following terms: heat of vaporization heat of fusion freezing melting vaporization condensation evaporation sublimation deposition

Warm-up Tues 9/2 Pick up a set of ‘States of Matter’ cards.  Match the properties to each state Before we can go on…  Friday’s work needs to be completed. You have 15min! Standards of Measurement (p.19-25) Unit (name) Unit (symbol) What does it measure? If units measure the same thing, what makes each unique? Keep adding rows as needed… You WILL have more than this! 3.Using p.19-25, create a table like the one below with the data you find there. 4.Below your table, define the following terms: heat of vaporization heat of fusion freezing melting vaporization condensation evaporation sublimation deposition

Warm-up Wed 9/4 Within 5min after the bell: 1. Pick up Matter states ‘cards’ (If you haven’t already.) 2. Get your notebook & find your new ASSIGNED seat 3. Cut up cards, mix, & practice putting them back in order 4. Review our previous notes Keep in mind…  Failure to do these tasks in a QUIET AND PROFESSIONAL MANNER will result in a Teacher Detention.  THIS IS YOUR WARNING!!! Behave in a way that EARNS you the respect you feel you deserve!

Pop Quiz! Put your notes away, but keep out something to write with. On your answer sheet, choose the correct response. We will exchange, grade, and discuss after.

Lab DEMO Instructions Review lab instructions as a class In the meantime:  Changes of States diagram & Temperature Conversions  RECALL: Standard Temperature is 0°C or 273 K  If given in Fahrenheit, you must convert first!  °F = (9/5)°C + 32  °C = (5(°F-32)) / 9 Remember order of operation rules  K = °C  °C = K – 273

Temperature Conversion Examples What is the Celsius value for 65° Fahrenheit? 200°C is the same temperature as what value on the Fahrenheit scale? Water boils at a temperature of 100°C. What would be the corresponding temperature for the Kelvin scale? A substance has a melting point of 625 K. At what Celsius temperature would this substance melt? Conversions from K to °F, or F to °K are rare, but possible. You can combine 2 formulas or use 2 steps.

Changes of States

Phase Change Diagram for Water Warm-up Fri.: Where should our phase change terms go?

Changes of Matter States 2 Types: Chemical & Physical Foldable! – Are these examples chemical or physical changes?  paint fading  pounding gold into a coin  boiling water  burning paper  rusting chain  condensation on your glass  ice cubes melting Left side- In your own words, use complete sentences to define chemical changes and physical changes. Be sure to record all of your examples.

Water Cycle Exit Ticket 9/4 On the left side of your ntbk., describe the physical change examples (we’ve discussed) shown here in the water cycle. Don’t forget to use complete sentences!

Water Phase Diagram This picture depicts the phases present at different temperatures and pressures. With pressure constant, the addition of heat will create a different graph.

TERMINOLOGY for PHASE CHANGES Sublimation - when a substance changes directly from a solid to a vapor  The best known example is "dry ice", solid CO 2 Deposition-when a substance changes directly from a vapor to a solid (opposite of sublimation)  Example-formation of frost Dynamic equilibrium - when a vapor is in equilibrium with its liquid as one molecule leaves the liquid to become a vapor, another molecule leaves the vapor to become a liquid. An equal number of molecules will be found moving in both directions  Equilibrium - When there is no net change in a system

TERMINOLOGY for PHASE CHANGES 2 types of boiling: boiling and evaporation  Evaporation takes place only at the surface of a liquid or solid while boiling takes place throughout the body of a liquid  Particles have high kinetic energy  Particles escape and become vapor Condensation-used to indicate changing from a vapor to a liquid

TERMINOLOGY for PHASE CHANGES Points to Know:  Melting Point-Temperature when solid turns to a liquid  Freezing Point-Temperature when liquid turns to a solid  Boling Point-Temperature when a liquid turns to a vapor  Doesn’t boil unitl vapor pressure coming off liquid is equal to the air pressure around it  Since air pressure changes with height, water does not always boil at 100°C  Condensing Point-Tempeature when vapor turns to liquid

GASES AND PRESSURE Pressure Conversions  Example 1: 421 torr = ? Atm  Step 1: Write what you know  Step 2: Draw the fence and place the given in the top left  Step 3: Arrange what you know from step 1 such that the nondesired units canceling out so that you are only left with the units you want (i.e. atm)  Step 4: Solve  Step 5: Report final answer taking into account the appropriate significant figures

TEMPERATURE Temperature is the measure of the average kinetic energy of the particles. 3 Units for Temperature:  Celsius  Farenheit  Kelvin  Has an absolute zero  Absolute lowest possible temperature  All particles would completely stop moving Temperature Conversions:  Example 1: Convert 35°C to °F  Example 2: Convert 300 Kelvin to °C

MEASURING PRESSURE Manometers:  Measure pressure  2 kinds: open and closed Open Manometers:  Compare gas pressure to air pressure  Example: tire gauge Closed Manometer:  Directly measure the pressure (no comparison)  Example: barometer

KINETIC ENERGY AND TEMPERATURE Energy of motion Energy of a moving object Matter is made of particles in motion Particles have kinetic energy KE = (mv 2 )/2 OR KE = (ma)/2 Kinetic Energy is measured in Joules  1 J = 1kgm 2 /s 2 The mass must be in kg The velocity must be in m/s OR acceleration must be in m 2 /s 2

KINETIC ENERGY AND TEMPERATURE Calculate the KE of a car with a mass of 1500 kg and a speed of 50 m/s

KINETIC ENERGY AND TEMPERATURE Calculate the KE of a car with a mass of 6780 grams and a speed of 36 km/h

KINETIC ENERGY AND TEMPERATURE Temperature-measure of the average kinetic energy of the particles Kelvin Scale:  Has an absolute zero (0K)  Absolute lowest possible temperature  In theory, all particles would completely stop moving Speed of Gases:  If two gases have the same temperature (particles moving at the same speed) how can you tell which gas has a greater speed?  The only difference is mass!  To find mass, use the periodic table

KINETIC ENERGY AND TEMPERATURE Speed of Gases  Example 1: If CH 4 and NH 3 are both at 284 K, which gas has a greater speed?  Step One: Add up the mass of each gas using the periodic table.  Step Two: The lighter gas moves faster (think about a race between a 100-pound man and a 700-pound man, the lighter man would move faster)  Example 2: Which gas has a faster speed between Br 2 and CO 2 if both are at 32°F?

TERMINOLOGY for PHASE CHANGES Melting-commonly used to indicate changing from solid to liquid  Normal melting point-The temperature at which the vapor pressure of the solid and the vapor pressure of the liquid are equal Freezing-Changing from a liquid to a solid Melting and freezing occur at the same temperature Liquifaction-Turning a gas to a liquid  Only happens in low temperature and high pressure situations

TERMINOLOGY for PHASE CHANGES Difference in Gas and Vapor  Gas-state of matter that exists at normal room temperature  Vaport-produced by particles escaping from a state of matter that is normally liquid or solid at room temperature Boiling-used to indicate changing from a liquid to a gas/vapor  Normal boiling point - temperature at which the vapor pressure of the liquid is equal to standard atmospheric pressure, which is kPa  Boiling point is a function of pressure.  At lower pressures, the boiling point is lower

ENTROPY A measure of the disorder of a system Systems tend to go from a state of order (low entropy) to a state of maximum disorder (high entropy) Entropy of a gas is greater than that of a liquid; entropy of a liquid is greater than that of a solid  Solids=low entropy; plasma=high entropy Entropy tends to increase when temperature increases  As substances change from one state to another, entropy may increase or decrease

Le CHATELIER’S PRINCIPLE Anytime stress is placed on a system, the sytem will readjust to accommodate that stress If a chemical system at equilibrium experiences a change in concentration, temperature, volume, or total pressure, then the equilibrium shifts to partially counteract the imposed change Can be used to predict the effect of a change in conditions on a chemical equilibrium Is used by chemists in order to manipulate the outcomes of reversible reactions, often to increase the yield of reactions

Le CHATELIER’S PRINCIPLE When liquids are heated (stress) they produce vapor particles (adjust) When liquids are cooled (stress) the particles inside tighten to form a solid (adjust)

Le CHATELIER’S PRINCIPLE Le Chatelier’s Principle explaining boiling and condensation using covered beaker partially filled with water  At a given temperature the covered beaker constitutes a system in which the liquid water is in equilibrium with the water vapor that forms above the surface of the liquid.  While some molecules of liquid are absorbing heat and evaporating to become vapor, an equal number of vapor molecules are giving up heat and condensing to become liquid.  If stress is put on the system by raising the temperature, then according to Le Châtelier's principle the rate of evaporation will exceed the rate of condensation until a new equilibrium is established

PHASE DIAGRAMS A diagram showing the conditions at which substance exists as a solid, liquid, or vapor Shows the temperature and pressure required for the 3 states of matter to exist Conditions of pressure and temperature at which two phases exist in equilibrium are indicated on a phase diagram by a line separating the phases Draw the phase diagram for water

PHASE DIAGRAM-WATER

Explanation of Phase Diagram:  X axis-Temperature (°C)  Y axis- Pressure (kPa)  Line AB – line of sublimation  Line BD – boiling point line  Line BC – melting point line  Point B – triple point (all 3 states of matter exist at the same time)  T m – melting point at standard pressure  T b – boiling point at standard pressure

HEAT in CHANGES of STATE Energy Diagrams (also referred to as Heating Curves)  Graphically describes the enthalpy (the heat content of a system at sonstant pressure) changes that take place during phase changes  X axis is Energy (Heat supplied)  Y axis is Temperature

HEAT in CHANGES of STATE Constructing Energy Diagrams  Step 1: Determine/Identify the melting and boiling points for the specified substance  Step 2: Draw x and y axis (energy vs temp)  Step 3: Calculations  First diagonal line: Q = mc  T  First horizontal line: Q = mH f  Second diagonal line: Q = mc  T  Second horizontal line: Q = mH v  Third horizontal line: Q = mc  T  Add up all values!!! Draw the energy diagram for 10 grams of water as it goes from –25°C to 140°C