 Matter and Temperature

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Matter and Temperature
Chapters: 2,3 and 14

Standards SPS2. Students will explore the nature of matter, its classifications, and its system for naming types of matter SPS2a. Calculate density when given mass and volume SPS5. Students will compare and contrast the phases of matter as they relate to atomic and molecular motion SPS5a. Compare and contrast the atomic/molecular motion of solids, liquids, gases and plasmas SPS5b. Relate temperature, pressure and volume of gases to the behavior of gases

Classifying Matter Matter: anything with mass and volume:
Atom: smallest unit of an element Element: cannot be broken down into anything simpler (by chemical means) ex hydrogen, oxygen, carbon…

Classifying Matter Molecule: two or more different elements chemically bound; smallest unit of a compound Compound: made up of molecules -formula ex NaCl

Pure Substances Fixed composition and definite properties
ex: water, salt, nitrogen, oxygen

Mixtures combination of substances:
-homogenous: parts are evenly distributed ex vinegar -heterogeneous: parts are not evenly distributed ex vegetables in a salad

Mixtures (cont’d) Miscible: can mix ex gasoline Immiscible: cannot mix
ex oil and water

Physical Properties of Matter
Physical Properties: can be observed without changing the identity of the substance ex melting point, boiling point, dissolving magnetism, ability to conduct electricity

Physical Properties (cont’d)
mass: amount of matter in an object volume: amount of space an object takes up density: ratio between mass and volume -D= m/V -measured in g/cm3 or g/mL m D V

Chemical Properties describes how a substance changes into another substance (cannot be reversed) ex flammability: ability to burn, reactivity: capacity to combine with another substance, rusting, effervescence (bubbling)

Matter and Energy Matter- anything that has mass and volume
4 states: solids, liquids, gases, plasma Energy- ability to do work: Potential Kinetic

Kinetic Molecular Theory
Kinetic Molecular Theory (KMT): All matter is made of constantly moving particles (atoms, molecules) All particles have kinetic energy (KE)

Temperature and Kinetic Energy
measure of average kinetic energy the more KE an object has, the higher its temperature Thermal energy= total KE; depends on: particle speed- faster particles have more KE number of particles- more particles have greater thermal energy

Thermal Energy Quiz A B Which beaker of water has more thermal energy?
B - same temperature, more mass 200 mL 80ºC A 400 mL B

States of Matter 1. solid: definite shape and volume 2. liquid: changes shape but not volume 3. gases: changes shape and volume 4. plasma: no definite shape or volume and full of moving charged particles

Energy and Solids Solids
low KE - particles vibrate but can’t move around definite shape, volume: *crystalline - repeating geometric pattern *amorphous - no pattern (e.g. glass, wax)

Energy and Liquids Liquids
higher KE - particles can move, but are still close together indefinite shape, not volume flows-fluid

Energy and Gases Gases high KE – particles move freely
indefinite shape and volume flows- fluid

Energy and Plasma Plasma
very high KE- particles collide with enough energy to ionize (break into charged particles) lacks definite shape or volume can conduct electric current (unlike gases) most common state of matter

Changes of State Releasing Energy
Condensation- gas to liquid Freezing- liquid to solid Temperature is constant during all changes in state of matter (ex: If energy is added to ice, the temperature of ice will not rise until all the ice has melted)

Changes of State Sublimation Evaporation Condensation Melting Freezing
substance does not change during a phase change, but the energy does.

Changes of State Requiring Energy
Melting Point: temperature at which a substance changes from a solid to a liquid Boiling Point: temperature at which a substance changes from a liquid to a gas

Energy Transfer Methods
Conduction: when objects in direct contact are unequal in temperature Convection: occurs in fluids (liquids or gases) -convection currents: rise and fall of fluids due to temperature differences (plate tectonics, wind) Radiation: transfer of energy by EM waves; no physical contact

Energy Transfer Heat: thermal energy that flows from a warmer material to a cooler material (energy transfer) -measured in joules (J)

Heat Transfer A B Why does A feel hot and B feel cold?
Heat flows from A to your hand = hot. Heat flows from your hand to B = cold. 80ºC A 10ºC B

Energy Transfer Conductor: material that can transfer energy easily as heat ex metals Insulator: material that cannot transfer energy easily ex. plastic, foam, wood

Temperature Scales T conversions: Fahrenheit: water boils- 212◦ F
water freezes- 32◦F Celsius: water boils- 100◦ C water freezes- 0◦ C ◦F = 1.8C ◦C = F – 32.0 1.8

Temperature Scales (cont’d)
Kelvin: based on absolute zero ( ◦C, when molecular energy is at a minimum) - theoretically, KE = 0 at absolute zero (but particles actually never stop moving!) K = ◦C Tκ = Tс + 273

Specific Heat T E = cmΔ Specific Heat (Cp)
amount of energy required to raise the temp. of 1 kg of material by 1 degree Kelvin units: J/(kg·K) or J/(kg·°C) E = cmΔ E =energy c = specific heat m = mass delta T = temp. change T

Specific Heat Practice
How much energy must be transferred as heat To 200kg of water in a bathtub to raise the water’s temperature from 25◦C to 37◦C? Given: Known: Solution: ΔT= 37◦C - 25◦C E = cmΔ T E= 4186J x 200kg x 12K ΔT= 12K kg·K m= 200kg E= 1.0 x 10⁴ kJ c= 4186 J

Law of Thermodynamics First Law of Thermodynamics: total energy used in any process is conserved Second Law of Thermodynamics: energy transferred as heat moves from higher T to a lower T - energy decreases in all energy transfers - entropy: measure of disorder within a system when left to itself

Heat Engines Heat engines: convert chemical energy to mechanical energy through combustion - mechanical energy: transferred by work - internal combustion: burns fuel inside engine; always generate heat

Fluids gases, liquids Exert pressure, bouyancy,
3 basic principles govern fluids: Archimedes’, Pascal’s, and Bernoulli’s

Pressure Amount of force exerted on a given area P = F A
SI unit = Pascal; 1P = 1N/m² Fluids exert pressure in all directions

Buoyant Force All fluids exert an upward buoyant force on matter
Due to increased pressure with increased depth

Archimedes’ Principle
Archimedes’ principle: buoyant force on an object in fluid is an upward force equal to the weight of the fluid that the object displaces

Buoyancy and Density Objects with D = 1.00g/cm³ or less will float

Pascal’s Principle Pascal’s principle: if pressure is increased at any point in a container, the pressure increases at all points by the same amount P₁ = P₂ or F₁ = F₂ A₁ A₂

Pascal’s Principle Practice
A hydraulic lift lifts a 19,000 N car. If the area of the small piston (A₁) equals 10.5 cm² and the area of the large piston (A₂) equals 400 cm², what force needs to be exerted on the small piston to lift the car? Given: Known: Solution: F₂ = 19,000N F₁ = F₂ F₁ = (F₂)(A₁) A₁ = 10.5 cm² A₁ A₂ A₂ A₂ = 400 cm² F₁ = (19,000N)(10.5cm²) F ₁ = ? 400cm F₁ = 500N²

Fluids in Motion Move faster in smaller areas than large ones
(think water through a partially blocked hose) Viscosity: the resistance of fluids to flow

Bernoulli’s Principle
Fluid pressure decreases as speed increases

Behavior of Gases Properties: Fill container Mix with each other
Low density Compressible (unlike solids or liquids, gases are mostly empty space)

Gas Laws Describe how the behavior of gas is affected by: Pressure
Volume Temperature (laws help predict the behavior of gases under certain circumstances)

Boyle’s Law Boyle’s Law: volume and pressure of a gas are inversely related P₁V₁ = P₂V₂ P₁ = initial pressure V₁ = initial volume P₂ = final volume V₂ = final volume P V

Boyle’s Law Practice A cylinder has a volume of 7.5 L and contains a gas at a pressure of 100 kPa. If the volume changes to 11 L, what is the final pressure? Given: Known: Solve: P₁ = 100 P P₁V₁ = P₂V₂ P₂ = P₁V₁ V₁ = 7.5 L V₂ V₂ = 11 L P₂ = (100 kPa)(7.5 L) P₂ = ? 11L P₂ = 68 kPa

Gay-Lussac’s Law P₁ = P₂ T₁ T₂
Gay-Lussac’s Law: pressure and temperature are directly related P₁ = P₂ T₁ T₂ P₁ =initial pressure T₁ = initial temp P₂ = final pressure T₂ = final temp P T

Charles’ Law T₁ = initial temp V₁ = initial volume T₂ = final temp
Charles’ Law: volume and temperature are directly related (at constant pressure) V₁ = V₂ V₁ = V₂ T₁ T₂ T₁ = initial temp V₁ = initial volume T₂ = final temp V₂ = final volume V T