Chapter 10: The Kinetic Theory of Matter

Section 10.1: Physical Behavior of Matter

Main Idea: The common states of matter are solid, liquid and gas

Compare characteristics of a solid liquid or gas

Relate the properties of a solid, liquid, and gas to the kinetic theory of matter

Distinguish among amorphous solids, liquid crystals, and plasmas

Based on properties: position and movement of atoms ions or molecules

Classification

has a fixed volume that cannot be compressed into a smaller volume

  is rigid with a definite shape because the

atoms, ions, or, molecules are in fixed positions

Solid

is flowing matter with a definite volume but an indefinite shape

  takes the shape of its container

Liquid

flowing, compressible matter that has no definite volume or shape

spreads out to fill the space 

particles are much farther apart than they are in solids and liquids

particles can be easily pushed together

Gas

Video on states of matter

Solid, Liquid and Gas

Robert Brown- 1827 Observed that particles in water (pollen

grains) move continuously in random, irregular directions

Definition: constant, random motion of tiny chunks of matter

https://www.youtube.com/watch?v=hy-clLi8gHg

Brownian Motion

Water molecules are not the only molecules that display random motion

Only Water???

states that submicroscopic particles of all matter are in constant motion

Kinetic energy is the energy of moving objects

Kinetic Theory of Matter

A gas particle can change direction only when it strikes the wall of its container or another gas particle

Assumptions: Each gas particle rebounds without losing kinetic energy and without losing speed, but in a new direction

Collisions of particles in a gas are called elastic collisions because no kinetic energy is lost

Kinetic Model of Gases

gas with particles that are in constant motion but have no attraction for each other. The particles undergo elastic collisions.

Except at very low temperatures or very high pressures, nearly all gases act as ideal gases

Ideal gas

Pressure is the force acting on a unit area of a surface Example: psi = pounds per in2

Particles in a gas exert a force on each square cm of the walls of the container when the wall deflects them

Earth’s atmosphere (mixture of gases) exerts pressure also. Constant bombardment of molecules in the air

Gas Particles and Pressure

Particles of a liquid can slide past each other, but they are so close together that they don’t move as straight as gas particles

Kinetic Model of Liquids

Strong forces between particles explain the rigid structure of solids

Particles of a solid cannot move past each other, but they are in constant motion (vibration)

  Particles occupy fixed positions in a well defined, 3-

dimensional arrangement

Crystal lattice- The arrangement, which is repeated throughout the solid

  When a solid melts, its crystal lattices disintegrate

and its particles lose their 3-dimensional pattern

Kinetic Model of Solids

Other forms of matter not classified as solids, liquids or gases

http://education-portal.com/academy/lesson/the-kinetic-

molecular-theory-properties-of-solids-and-liquids.html#lesson

Haphazard, disjointed, and incomplete crystal lattice

Examples: candle wax, cotton candy, peanut butter

https://www.youtube.com/watch?v=bzr-byiSXlA

Amorphous Solid

materials that lose their rigid organization in only one or two dimensions when they melt

  interparticle forces in a liquid crystal are relatively

weak and their arrangement is easily disrupted  When the lattice is broken, the crystal can flow like

a liquid  Liquid crystal displays (LCDS) are used in watches,

calculators, etc. because they can change colors at specific temperatures

https://www.youtube.com/watch?v=nAJgchCI3kg

Liquid Crystal

an ionized gas that forms at very high temperatures  most common form of matter in the universe but

least common on Earth (sun and stars)  can conduct electrical current and are electrically

neutral (contain equal numbers of free electrons and positive ions)

  are called high-energy states of matter because

high energy is needed to separate and to maintain separation of the atoms into ions and electrons

Plasma

Predicted by Einstein in 1924, Created in 1995 (CU Boulder- Cornell/ Weiman)

  a rare state (or phase) of matter that occurs at

extremely low temperature, near the value of absolute zero (at zero- no particles move)

Superfluid helium-4 that involve Bosons https://www.youtube.com/watch?

v=nAGPAb4obs8

Bose-Einstein Condensate (BEC)

In the July 14, 1995 issue of Science magazine, researchers from JILA reported achieving a temperature far lower than had ever been produced before and creating an entirely new state of matter predicted decades ago by Albert Einstein and Indian physicist Satyendra Nath Bose. Cooling rubidium atoms to less than 170 billionths of a degree above absolute zero caused the individual atoms to condense into a "superatom" behaving as a single entity. The graphic shows three-dimensional successive snap shots in time in which the atoms condensed from less dense red, yellow and green areas into very dense blue to white areas. JILA is jointly operated by NIST and the University of Colorado at Boulder.

Highlight vocabulary or unknown words. Circle any examples you had written down Write 3 questions.

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