Skip this Video
Download Presentation
The Kinetic Theory of Matter explains the properties of solids, liquids, & gases

Loading in 2 Seconds...

play fullscreen
1 / 38

The Kinetic Theory of Matter explains the properties of solids, liquids, & gases - PowerPoint PPT Presentation

  • Uploaded on

The Kinetic Theory of Matter explains the properties of solids, liquids, & gases. The Kinetic Theory of Matter. Based on idea that particles of matter are in constant motion. Describes properties of solids, liquids, & gases in terms of the FORCE of the particles

I am the owner, or an agent authorized to act on behalf of the owner, of the copyrighted work described.
Download Presentation

PowerPoint Slideshow about ' The Kinetic Theory of Matter explains the properties of solids, liquids, & gases' - donagh

An Image/Link below is provided (as is) to download presentation

Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author.While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server.

- - - - - - - - - - - - - - - - - - - - - - - - - - E N D - - - - - - - - - - - - - - - - - - - - - - - - - -
Presentation Transcript
the kinetic theory of matter
The Kinetic Theory of Matter

Based on idea that particles of matter are in constant motion.

Describes properties of solids, liquids, & gases in terms of the FORCE of the particles

The constant random motion of tiny particles called Brownian motion

states of matter
States of Matter
  • Four states of matter
  • Particles-closely packed; can’t be compressed
  • Voids - extremely small
  • Particle motion is vibratorymotion; definite shape & volume
  • Apply heat-particles vibrate more & move SLIGHTLY farther apart; causes solid to expand
kinetic model of solids
Kinetic Model of Solids

STRONG intermolecular forces result in rigid structure of solids

Particles move (vibrate) but not past each other

Particles occupy fixed 3-D positions that repeat throughput the solid

3-D arrangement = crystal lattice

  • Flowing matter w/ definite volume & indefinite shape
  • Particles have weak bonds that keep them close; more space to move; particles able to move relative to each other
  • When heat applied, liquids expand a little
kinetic model of liquids
Kinetic Model of Liquids

Particles of liquid slide past each other; consider magnetized spheres

Intermolecular forces maintain their volume NOT shape

  • Flow, too (consider wind)
  • Particles far apart; complete freedom of movement
  • Motion is random
  • No definite shape/volume
  • Easily compressed into smaller volume
  • Expand & contract in response to temperature changes more so than liquids & solids
kinetic model of gases
Kinetic Model of Gases

Particles in gas in constant, random motion

Change direction ONLY when they strike wall of container OR another gas particle (Air-hockey puck)

Density (M/V) in gas lower than solid

Few particles in gas vs solid of same volume (due to space between particles)

5 assumptions of the kinetic theory
5 Assumptions of the Kinetic Theory

Gases are made of molecules in constant, random movement.

LARGE portion of the volume of a gas = empty space. The volume of all gas molecules, in comparison, is negligible.

5 assumptions of the kinetic theory1
5 Assumptions of the Kinetic Theory

The molecules show no forces of attraction or

repulsion (UNLIKE solids & liquids).

No energy is lost in collision of molecules; the impacts are completely elastic.

The temperature of a gas is the average KE of all of

the molecules.

ideal gases
Ideal Gases
  • Ideal gases = gases that obey the assumptions of the kinetic theory
  • Except for temperatures extremes, most real gases behave like ideal gases
  • At temperature extremes, forces between particles & particle size begin to matter
  • At temperature extremes gases no longer follow the assumptions of the kinetic theory
gases pressure temperature volume
Gases & Pressure, Temperature, & Volume
  • KToM explains gas pressure = the total force exerted by gas molecules colliding against the walls of a container.
  • IF the container can expand, like a balloon/tire,

in pressure can the volume; THUS the balloon/tire will get BIGGER .

  • If you the temperature of the gas, the KE of its molecules &, the pressure/volume
gases pressure temperature volume1
Gases & Pressure, Temperature, & Volume
  • There is a relationship between pressure, volume and temperature in an ideal gas
  • If you the pressure & hold the volume constant, the temperature (principle of a refrigerator)
  • If you the temperature & hold the pressure constant, the volume (heating a balloon)
earth s atmosphere and pressure
Earth’s Atmosphere and Pressure
  • We’re at the bottom of an ocean of air
  • Atmospheric pressure = force exerted on us by molecules of air (14.7 lbs/square inch)
  • Atmospheric pressure related to column of air;
  • As elevation ↑ pressure↓
  • As elevation ↓, pressure ↑
  • How does atm pressure affect YOU?
other forms of matter
Other Forms of Matter
  • Amorphous Solids = arrangement of molecules is fairly random; so, crystal lattice is loosely packed ; haphazard, disjointed
  • Examples = GLASS,

cotton candy


liquid crystals
Liquid Crystals
  • When solids melt, the crystal lattice disintegrates; particles lose their 3-D pattern
  • Liquid crystals-NOT liquid OR solid
  • When melted LCs lose their rigid organization in 1 or 2 dimensions NOT all 3 dimensions
  • Interparticle forces in liquid crystals are relatively weak; when forces in lattice are broken, crystals can flow like liquids
  • Liquid crystal displays (LCDs) used in TVs, watches, calculators, thermometers, etc.
  • Form at very temperatures
  • Plasma = gas that has been energized; some e- break free from, but travel w/their nucleus
  • Plasma = free e- & ions of that element.
  • Gases can become plasmas in several ways, ALL include pumping the gas w/ energy.
  • Examples = stars, fluorescent tubes, neon lights, etc.
temperature kinetic energy particle motion
Temperature & Kinetic Energy & Particle Motion
  • Temperature = measure of the average kinetic energy of particles in a material
  • When heated liquid & gas particles have more kinetic energy BUT not all particles have the same kinetic energy; particles are moving at different speeds
  • Generally, as temperature matter moves to a more active state; as temperature matter moves to a less active state
the kelvin scale
The Kelvin Scale
  • Absolute zero = temperature at which a substance would have zero (or very little) kinetic energy
  • Kelvin Scale = used for temperature; it is defined so temperature of a substance is directly proportional to the average kinetic energy of the particles
  • 0 on Kelvin scale = absolute zero & measured as Kelvins; divisions on Fahrenheit & Celsius scale are measured in degrees
  • Celsius degree & Kelvins = the same size; absolute zero = -273.150C
  • Kelvin scale measures everything ABOVE absolute zero; all numbers are positive
temperature conversions
Temperature Conversions
  • When converting from kelvin (K or TK) to Celsius (C or TC), and vice versa, the magic number is 273!!
  • K= (0C+ 273); K= (150C+ 273) = 288 K
  • 0C= (K- 273); 0C= (320 K - 273) = 470C
mass speed of particles
Mass & Speed of Particles

KE of gas depends on mass & speed of particles

1. Gases at SAME temp have SAME average KE

2. LARGER gas molecule simply moves SLOWER than SMALL gas molecule

Ex: O2 = 16x more massive than H2; at SAME temp, H2 moves FASTER than O2

mass speed of matter
Mass & Speed of Matter
  • Random motion causes particles to spread out to fill a container
  • DIFFUSION = the process in which these particles fill a space
  • Particles move from areas of high concentration to areas of low concentration
  • Rate of diffusion of a gas dependent upon the KE of that gas/substance
changes of state
Changes of State

TRIPLE POINT = The single specific temperature & pressure at which all 3 phases can co-exist

CRITICAL POINT = The conditions where gas & liquid become indistinguishable

Different phases of a system may be represented using a phase diagram.

Axes of the diagrams are typically pressure & temperature

changes of state1
Changes of State
  • particles of a liquid form a gas by escaping from the surface
  • 3 things affect evaporation rate? Area of the surface, temperature, humidity
  • Volatile liquids evaporate quickly (perfumes, paint)
  • As liquids evaporate, they cool

Heating Curve-based on standard temp & pressure

changes of state2
Changes of State


The process of heating a SOLID substance to a point where it turns LIQUID.

FREEZING is the opposite of melting. It is the process of REMOVING heat from a liquid & turning the liquid into a solid.

The freezing point is the SAMETEMPERATURE as the melting point.

Heating Curve-based on standard temp & pressure

changes of state3
Changes of State
  • Sublimation-process by which particles in a solid change to gaseous state w/o melting
  • Condensation-reverse of evaporation; gaseous particles become close (condense) & form a liquid
specific heat
Specific Heat
  • To change the temperature of a SOLID

2.1 Joules/g0C

  • To change the temperature of a LIQUID

4.2 Joules/g0C

  • To change the temperature of a GAS

2.02 Joules/G0C

Heat = mass x specific heat x temperature change

Q = m x c x (Tf –Ti)

heat of vaporization
Heat of Vaporization
  • The amount of heat required (absorbed by the liquid) to convert unit mass of a liquid into its vapor w/o a change in temperature.
  • 2260 Joules = ENREGY needed to move the molecules in 1 g of water FAR enough apart that they form water vapor (JOULE, J,= SI unit of energy required to lift a 1-g mass 1m against the force of gravity)
  • Heat of Vaporization (Hv) of H2O = 2260 J/g
heat of vaporization of water hv 2260 j g
Heat of Vaporization of Water Hv = 2260 J /g
  • The diagram right shows the uptake of heat by 1 kg of H2O, from ice at -50 ºC  to steam above 100 ºC.

A: Rise in temp. as ice absorbs heat.B: Absorption of latent heat of fusion.C: Rise in temp. as liquid H2O absorbs heat.D: Water boils & absorbs latent heat of vaporization.E: Steam absorbs heat & thus increases its temperature.

heat of fusion
Heat of Fusion
  • The heat nrg which must be removed to solidify a liquid or added to melt a solid
  • Melting point=temperature of the solid when its crystal lattice begins to break apart (intermolecular forces are overcome & solid becomes a liquid)
  • Freezing Point= temperature of liquid when it begins to form a crystal lattice & becomes a solid