Presentation on theme: "States of Matter: Kinetic Molecular Theory Holt McDougal Physical Science C3S1: Matter and Energy Glencoe Science Physical Science C16S1: Kinetic Theory."— Presentation transcript:
States of Matter: Kinetic Molecular Theory Holt McDougal Physical Science C3S1: Matter and Energy Glencoe Science Physical Science C16S1: Kinetic Theory
NGSSS Benchmark(s) SC912P12.11 Describe phase transitions in terms of kinetic molecular theory SC912P8.1
Learning Objectives What makes up matter? What is the difference between a solid, a liquid, and a gas? What kind of energy do all particles of matter have? How do particles move in the four states of matter? How do particles behave at the melting and boiling points of matter?
Characteristics of Matter Has mass Has volume Made of atoms Atoms in constant motion
Kinetic Molecular Theory of Matter All matter is made of particles that are in constant motion Stuff is moving all the time
Kinetic Theory 2 The faster particles move, the higher the temperature of the substance. Fast moving stuff is hotter than slow moving stuff.
Kinetic Theory 3 At the same temperature, more massive particles move more slowly than less massive ones. Big stuff is slower than small stuff at the same temperature.
What explains how particles in matter behave? A.Law of Conservation of Mass B.Law of Kinetic Movement C.Kinetic Molecular Theory D.None of the above
What is Thermal Energy? Energy ability to change/move matter Total energy of the particles in a material TE = KE + PE If temperature is lowered, particles will have less thermal energy
Average Kinetic Energy Temperature avg of how fast particles are moving Molecules have kinetic energy at all temperatures (even absolute zero)
What two things comprise thermal energy? A.Potential movement and Kinetic energy B.Kinetic movement and Potential energy C.Potential movement and Kinetic movement D.Potential energy and Kinetic energy
Common States of Matter Solid, liquid, gas Definite something does not change Variable something can change
Solids Definite volume Definite shape Strong attraction keeps particles in place Particle arrangement establishes chemical and physical properties
Solid to Liquid: How? Melting point temp for solid to begin turning to liquid Particles slip out of ordered arrangement Heat of Fusion amt of energy needed to change a substance from a solid to a liquid at its melting point
Liquid to Gas: How? Particles have enough energy to escape attractive forces Evaporation particles at surface & travel away Boiling point temp at which pressure of the vapor in the liquid = external pressure on surface of liquid Heat of vaporization amt of energy needed for liquid at its boiling point to become a gas
How would you respond? What is the temperature at which a solid begins to turn into a liquid called? Which particles have the least kinetic energy? What do particles need in order to overcome the force of pressure and become a gas? How does the movement of particles in a liquid differ from the movement of particles in a solid? What causes a solid to have a definite volume and shape?
Fluid: What is it? State of matter with variable shape Liquids Gases
Plasma Matter made up of positively and negatively charged particles (i.e., ionized particles) Neutral Conducts electricity Stars, lightning bolts, neon and fluorescent tubes, auroras
Thermal Expansion Increase in the size of a substance when the temperature is increased Hot stuff moves faster and takes up more space.
Solid or Liquid: Which? Amorphous solid no melting point; soft over a range of temperatures Glass Plastic Liquid Crystals maintain ordered structure from solid to liquid state
What do you think? Describe the movement of particles in a fluid. Is plasma a fluid? Explain your answer. Why do all particles of matter have kinetic energy? Which of the three common states of matter has particles with the most kinetic energy? Why do all particle of matter have kinetic energy? What does temperature measure?
Changes of State of Matter Holt McDougal Physical Science C3S2: Matter and Energy
Learning Objectives What happens when a substance changes from one state of matter to another? What happens to mass and energy during physical and chemical changes?
What Causes Matter to Change States? Change of state from one physical form to another Caused by transfer of energy Identity of substance remains the same
Adding and Removing energy Heating adds energy Adding NRG causes particles to move more quickly Removing NRG causes particles to move more slowly
Temperature and Energy Adding NRG increases kinetic energy of the particles Removing NRG decreases kinetic energy of the particles Temperature measure of the avg kinetic energy
Think fast! What does hot mean for temperature? What will removing all kinetic energy do to a gas?
Changes of State That Require Energy Melting from solid to liquid Melting point particles have enough nrg to break from rigid positions Melting point can change if pressure changes
Evaporation Change from liquid to gas Boiling evaporation at specific temp and pressure Boiling point temp at which liquid boils
Sublimation Change from solid to gas Example: Solid CO2 –(room temp) Gas CO2
Whats Your Answer? What are three changes of state that require energy? Melting Boiling Subliming
Changes of State That Release Energy Condensation from gas to liquid Condensation point temp to chg from gas to lqd Condensation often happens when gas touches cool surface (e.g., vapor touches cold glass and becomes water droplets)
Freezing Point Freezing chg from lqd to solid Freezing point temp at which substances freezes Freezing point = Melting point = Freezing point Add nrg to melt; release nrg to freeze
Do you recall? What is the condensation point? What is the melting point? What is the boiling point? What is the melting point? What is the point?
What Happens to Temperature During Changes of State? Temp does NOT chg during a chg of state When a substance loses or gains energy, either its temperature change or its state changes... (The) two changes do not happen at the same time. (p. 51)
By the Way: Helpful Links htmlhttp://www.chem4kids.com/files/matter_intro. html mechanics/energy/heatAndTemperature/chang esOfPhase/changeOfState.htmlhttp://zonalandeducation.com/mstm/physics/ mechanics/energy/heatAndTemperature/chang esOfPhase/changeOfState.html
What Happens to Mass and Energy During Physical and Chemical Changes? Law of Conservation of Mass Law of Conservation of Energy Conserve to keep the same
Fluids Holt McDougal Physical Science C3S3: States of Matter Fluids
Learning Objectives How do fluids exert pressure? What causes objects to float? What happens when pressure in a fluid changes? What affects the speed of a fluid?
What Are Fluids Liquids and gases Particles can move past each other Exert pressure in all directions
What Is Pressure With your neighbor, come up with a quick demonstration of pressure... Pressure amt of force exerted on a give surface area
Calculating Pressure Divide force by area Pressure = Force/Area; P=F/A Pascal SI unit for pressure Newton SI unit for force 1 Pa = 1 N/m 2
Try Calculating Pressure Given a force of 20N over 60m 2, how much pressure is being exerted? Try this on your whiteboard. Write the formula:P = F / A Substitute values:P = 20N/60m 2 Divide the units:P = N/m 2 Now, divide the quantities:20/60=.33 Assemble the answer:P = 0.33N/m 2
What Causes an Object to Float? Buoyant force upward force fluids exert on matter Archimedes Principle The buoyant force of an object equals the weight of the fluid that the object displaces.
Do you remember... What is pressure? The amount of force exerted over an area What is a Pascal? The SI unit for pressure; 1Pa = 1N/m 2 Given area and pressure, how does one determine the number of Newtons required? Since P=F/A, then F = P * A
Will It Sink or Float? By WeightBy Density Compare weight to buoyant force why? Floats bouyant force > or = objects weight Sinks bouyant force < or = objects weight Compare density of object to density of fluid Floats object is less dense than the fluid Sinks object is denser than the fluid BTW, the density of water is... 1 g/cm 3 astr.gsu.edu/hbase/hframe.html
What Happens When Pressure Changes in a Fluid? What happens when you squeeze a balloon? What happens when you squeeze a tube of toothpaste? Pascals principle If the pressure in a container is increased at any point, the pressure increases at all points by the same amount.
Pascals Principle (formula) P(1) = P(2) If P = F / A, then what does F(1) / A(1) equal? F(1)/A(1) = F(2)/A(2) Remember, pressure is measured in pascals and 1Pa = 1N/M 2
Hydraulic Devices and Pascal Use liquids to transmit pressure from one point to another Car lift Beautician chair Barbershop
Apply Pascals Principle to Solve A hydraulic lift uses Pascals principle to lift a 19,000N car. The area of the small pistons equals 10.5cm2 and the area of the large piston equals 400 cm2. What force must you exert on the small piston to lift the car? Write formula Substitute Do the math
Properties of Fluids in Motion Fluids and area Fluid pressure and speed Viscosity
Fluids and Area What happens when you put your finger over the opening for a water/garden hose? If the flow rate stays the same, fluids move faster through small areas than large areas.
Bernoullis Principle Swiss Scientist from 1700 to 1782 Published his discovery in 1738 Blow across top of paper As the speed of a fluid increases, the pressure exerted by the fluid decreases.
Quiz: Write Questions and Answers 1.How can you use density to determine if an object will float in a fluid? 2.You put a small object into a cup of water and the displaced water weighs 235N. What is the buoyant force on the object? Explain your answer. 3.How does a hydraulic device multiply force? 4.A balloon filled with helium floats in the air. What does this tell you about the density of helium? 5.How are speed and pressure of a fluid related? 6.How do the attractions between particles in a fluid determine viscosity?
Fluid Flow Viscosity Viscosity fluids resistance to flow Think about the principles of Kinetic Molecular Theory; why are some fluids more viscous than others? In general, the stronger the attraction between the particles of a fluid, the more viscous the fluid is.
NGSSS and Learning Objective Questions SC912P12.10 Interpret the behavior of ideal gases in terms of kinetic molecular theory What are some properties of gases? How do changes of pressure, temperature, or volume affect a gas?
Physical Properties of Gases What are some physical properties of Gases? Class Notes these properties: Expand to fill their containers Easily mix with one another Have low densities Can be compressed Are mostly empty space Exert pressure on their containers
Gas Laws Boyles Law variable volume Gay-Lussacs Law variable pressure Charless Law variable temperature
Boyles Law Works if temperature and amount of gas are constant or unchanged For a certain amount of gas at a constant temperature, the volume of a gas decreases as the gass pressure increases. Likewise, the volume of a gas increases as the gass pressure decreases. P1V1 = P2V2
Practice Boyles Law Given a balloon with a volume of 7.5L at kPa, what is the pressure of the balloon when the volume is 11.0L? 1.Write the formulaP1V1=P2V2 2.Substitute values7.5(100)=P2(11.0) 3.Multiply750=11.0(P2) 4.Divide 750/11.0=11.0(P2)/ Assign correct units68kPa
Try Boyles Law, again A 300mL sample of H gas is at a pressure of 0.500KPA. If the pressure increases to 0.750kPa, what will be the final volume of the sample? Assume that temperature stays constant. 1.Write the formula 2.Substitute values 3.Multiply 4.Divide 5.Assign correct units
Think About It... What might happen if you threw a full can of spray paint into a raging fire?... remember the container is rigid, so its volume cannot increase!
Pressure and Temperature Temperature measure of avg kinetic nrg Increase temp particles gain kinetic nrg and bump sides of container more often Increase temp pressure increases
Gay – Lussacs Law When volume is constant, the pressure of a gas increases as temperature increases. Pressure decreases as temperature decreases. Pressure and temperature = directly related. Change one = same kind of change in the other
Charless Law: Its the Kinetic Theory!!! A scientist named Jacques Charles did many experiments involving gas volumes and temperatures. If gas and pressure are constant, the volume of gas increases as temperature increases. V=Tk (where k is a constant pressure).
How Can Graphs Illustrate the Gas Laws? Graphs show relationship between two factors Direct relationship two variables change in the same direction Inverse relationship variables change in opposite directions Straight line directly proportional Curved line variables dont maintain ration