STATES OF MATTER The Four States of Matter Four States Solid Liquid Gas Plasma.
States of Matter...Four States of Matter Solids –low KE - particles vibrate but can’t move...
Transcript of States of Matter...Four States of Matter Solids –low KE - particles vibrate but can’t move...
Kinetic Theory
States of Matter
– Kinetic Molecular Theory
– Four States of Matter
– Thermal Expansion
Chapter 16 Lesson 1
Kinetic Molecular Theory
KMT
– Tiny, constantly moving particles make up all matter.
– The kinetic energy (motion) of these particles increases as temperature increases.
– These particles are colliding with each other and the walls of their container.
Four States of Matter
Solids – low KE - particles vibrate but
can’t move around
– atoms held tightly into place
– definite shape & volume
Four States of Matter
Liquids – higher KE - particles can move
around but are still close together
– indefinite shape
– definite volume
Four States of Matter
Gases – high KE - particles can separate
and move throughout container
– indefinite shape & volume
– move more quickly than particles that make up solids
Four States of Matter
Plasma – very high KE - particles collide with
enough energy to break into charged particles (+/-)
– gas-like, indefinite shape & volume
– stars, fluorescent light bulbs, TV tubes
Phase Changes
Heat of fusion-melting – solid to liquid.
– energy required to change a substance from the solid phase to the liquid phase at its melting point is known as the
– some attractive forces are broken
Freezing – liquid to solid
melting point = freezing point
Phase Changes
Heat of vaporization – energy required for the
liquid at its boiling point to become a gas.
– all attractive forces are broken
– EX: steam burns, sweating, and… the drinking bird
Thermal Expansion
Most matter expands when heated & contracts when cooled.
Temp causes KE. Particles collide with more force & spread out.
EX: thermostats (bimetallic strip)
Heating Curves
Kinetic Energy – motion of particles
– related to temperature
Potential Energy – space between particles
– related to phase changes
Solid or a Liquid?
Amorphous solids and liquid crystals
– two classes of materials don’t react as expected when changing states.
– solids soften and gradually turn into a liquid over a temperature range
– lack the highly ordered structure found in crystals
– are typically long, chainlike structures that can get jumbled and twisted
The Strange Behavior of
Water Water molecules
– unusual in that they have highly positive and highly negative areas
– charged regions affect its behavior
– as the temp drops the particles move closer together
The Strange Behavior of Water
Freezing water molecules
– unlike charges are attracted to each other and line up so that only positive and negative zones are near each other.
– water molecules orient themselves according to charge, empty spaces occur in the structure.
– these empty spaces are larger in ice than in liquid water, so water expands when going from a liquid to a solid state.
Liquid Crystals
LCD
– flow during the melting phase similar to a liquid, but they do not lose their ordered arrangement completely.
– placed in classes depending upon the type of order they maintain when they liquefy
– are highly responsive to temperature changes and electric fields.
– ex: televisions, watches, clocks, and calculators