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Notes: Properties of Solids,
Liquids, Gasses, and Kinetic
Theory
Gasses, Pressure, Kinetic Theory,
Temperature, Pressure, Heating Curve,
Diffusion
Gas Diffusion Activity
• Cologne or perfume particles:
Could you smell the particles as soon as the bottle
was opened?
Who could smell the cologne first? Last?
Describe how the cologne moved through the room
over time
Draw some “maps” of the room mapping the
movement of the cologne or perfume particles
at 1s, 60s, 5 min, 15 min and 30 min.
Is there a pattern of movement of the particles?
Diffusion Activity
• Observe the food coloring in the water
Compare & contrast what happens when the food
color is put in the hot water and the cold water.
Note how fast or slow the color moves in the cold
water vs. the hot water.
Diffusion of Gasses • To see the diffusion animation click this link:
– Diffusion is a term that refers the tendency of particles in a
fluid (gasses & liquids) to spread out and mix in with their
surroundings.
– This usually happens because everything moves from high to low.
– In this case from high concentration (as in a bottle of perfume) to low concentration (as in a room full of air with no perfume mixed in).
• If a perfume bottle is opened into the air and mixes with the air what is the solute & what is the solvent??
– The mixing is caused by the motion of the solvent particles. Solute: thing present in the smaller quantity, being mixed or dissolved. Solvent: thing in the greater quantity that is doing the mixing or dissolving.
Diffusion
Bell Work, Chemistry, Bell Work, Monday, Oct 17, 2016
PhET –States of Matter, Basic
States of Mater
http://www.chm.davidson.edu/vce/KineticMolec
ularTheory/Diffusion.html
Diffusion
https://authoring.concord.org/activities/1067/single_page/38493916-b8ba-4824-9457-
b27c00ce543d
States of Mater Animation
Densities of Solids , Liquids, & Gases What do we know about how our particles arrange themselves in solids, liquids & gasses ? What is this property called?
• The solid particles are very close together (very dense).
• The liquid particles are not as dense as a solid but are
still close together,
• The gas particles are very spread out.
This property is called density.
Solid Liquid Gas
States of Matter
Which diagram represents the solid state, the liquid state
and the gas state of matter. Explain your answer.
A B C
A: Solid - definite
shape & volume.
Distance between
the particles is
negligible.
B: Liquid - no definite shape but definite volume. Particles close together and slide by each other.
C: Gas - no definite
shape, no definite
volume. Particles very
far apart.
States of Water
• A lattice is a regular repeating geometric pattern
• The solid, b, is composed of hexagons
• Remember, ice floats in water
• Remember, the less dense substance floats!!
liquid solid gas
States of Matter Solid, Liquid, Gas
• Click the links below to see the States of Matter animation and simulations
• States of Matter Simulation
States of Mater Animation
Solids, liquids and Gasses
1. Describe the solid, liquid and gas.
gas liquid solid
shape
compres-
sible
Flows or
moves
Assumes the shape and volume of its container. Particles can move past one another.
assumes the shape of the part of the container which it occupies. Particles can move/slide past one another.
retains a fixed volume and shape (lattice) rigid - particles locked into place.
Compressible, lots of free space between particles
not easily compressible, little free space between particles
not easily compressible, little free space between particles
flows easily, particles can move past one another
flows easily, particles can move past one another .
Vibrates, Rigid - particles cannot move/slide past one another
Phase Changes • Phases are states of matter: solid, liquids and gas.
• Phase change means solid turns into liquid, liquid to gas.
• Melting – breakdown of order where the mutual forces of attraction are no longer strong enough to maintain lattice structure due to molecules moving faster and faster from heating. The solid turns into a liquid.
• Evaporation – when molecules escape from a liquid the spread out in all directions and become gas or vapor
• Boiling – the temperature at which the vapor pressure of a liquid equals the atmospheric pressure. At the boiling point, molecules through out the liquid have enough energy to vaporize (turn into gas).
• Condensation – When gas molecules slow down and crowd together (due to attractions) more densely to form a liquid
• Freezing – When liquid molecules slow down due to heat loss, they become attracted to each other through a mutual force of attraction and begin to “stick together” in a regular geometric pattern (lattice). Thus, the liquid turns into a solid.
• Molecules are sticky particles.
• If the molecules slow down, they will begin to stick together and gases will become liquids. If the slow down more, liquids will stick together even further and become solids.
Whooshies
Using particle diagrams, represent samples of a cold gas
and a hot gas. Speed is shown by the length of the
whooshies.
slow particle: fast particle:
Temperature
Alcohol Thermometer
How Does a Thermometer Work? Objective: Describe the ways that energy is transferred between the system and the surroundings. Explain pressure.
1. Q = heat, fluids are liquids & gasses
• the circle is the thermometer (the system), the square is the fluid (the surroundings).
2. Heat always flows from: – hot to cold (high to low)
COLDER
WARMER
COLDER
WARMER
THERMOMETER
FLUID:
THERMOMETER
FLUID:
Diagram on the left: heat flows from hotter fluid into the colder thermometer.
Diagram on the right: Heat flows from the hotter thermometer into the colder fluid.
Thermometer in Warmer Fluid
1 2 3
1. Heat flows into thermometer from fluid.
2. Molecules in thermometer speed up.
3. Molecules in thermometer expand.
- 273
Heat and Temperature. • Temperature = speed of molecules. Faster is
hotter, slower is colder. • Temperature does not depend on mass (how much stuff
there is).
• Heat of a substance involves temperature and
mass.
• Heat depends on the degree of hotness (also
called temperature) and how much stuff there is
(mass).
• mass is equivalent to the number of particles • A bucket of 50º water has more heat in it than a tea cup of 100º
water because of greater mass & temperature not to far apart.
Chemistry, Exit Ticket, Wednesday, Oct 29, 2014 2. Explain why the mercury or alcohol level in a thermometer rises when it is placed in a warmer fluid. (3-step process)
1. Energy from the warmer fluid (the surroundings) is
transferred to the liquid in the thermometer.
2. This energy causes the alcohol molecules to move faster.
3. The alcohol molecules move further apart (expand).
Result: alcohol rises in the tube.
3. Explain why the mercury or alcohol level in a thermometer falls when it is placed in a warmer fluid. (3-step process).
1. Energy from the warmer thermometer is transferred to the
fluid (the surroundings).
2. This energy loss causes the alcohol molecules to move slower.
3. The alcohol molecules move closer together (contract).
Result: alcohol goes down in the tube.
Whooshies
Using particle diagrams, represent samples of a cold gas
and a hot gas. Speed is shown by the length of the
whooshies.
slow particle: fast particle:
Atmospheric pressure
760 mm Mercury or 29.92 inches Hg
Pressure 1. Define pressure: the amount of force exerted per unit area
of a surface.
Explain why the railroad tanker car was crushed. Clink the link to
see the
simulation of
pressure, volume
and temperature.
Gas Labs
P, V, T, n (# of particles) are related Draw representations of the particles in the box
that correspond to the shown positions along the graph. Use “whooshies” to show temperature.
1
2
3
3
2
1
3
2
1
Gas Labs P, V, T, n (# of particles) are related.
1
3
2
Draw representations of the
particles in the box that
correspond to the shown
positions along the graph. Use “whooshies” to show
temperature.
Gas Labs
Temperature
and number
of particles
are constant
Temperature
and volume
are constant
n = 100
P = 1 atm
n = 200
P= 2 atm
n = 300
P=3 atm
volume and
number of
particles are
constant
Temperature, (K)
Pre
ss
ure
Relationships on Graphs
1. What is meant by “directly related.” A straight line with a positive slope. (x gets bigger, y gets bigger) 2. What is meant by indirectly related? A straight line with a negative slope. (x gets bigger, y gets smaller) 3. What is meant by inversely related? x increases as y decreases, or x increases as y decreases
y
x y
x
A. directly
related or
direct
relationship
B. indirectly
related or
indirect
relationship
Sketch the Graphs
C. inverse
relationship (x
gets bigger, y
gets smaller)
A
B
C y
x
3. Determine the correct relationship for the graphs.
Objectives
1. P, V, T, & n are related:
Predict the effect of changing P, V, n or T on any of the
other variables.
𝐏 ∝ n, P ∝𝟏
𝑽, 𝑷 ∝T, V ∝ T
2. Explain (in terms of the collisions of particles) why the
change has the effect you predicted.
• P = pressure
• V= volume
• T = temperature
• n = number of particles
Relationships 1. Predict the effect of changing P, V or T on any of the
other variables.
𝐏 ∝ n
a. If P doubles then V will; decreases ½ (÷ 2),
c. If P decreases by 1/3 then V will; d. If P increases by 3 then V will
triple
e. If T triples P will: f. If P triples, T will
triple triple
g. if T doubles then V will; h. if T decreases 1/3 then V will
double decrease by 1/3
i. if n triples then P will; j. if P quadruples then n will triple Quadruple (x 4)
b. If V decreases by ½ , P will
double
decrease by 1/3 (÷ 3)
The Relationship Between Pressure (P), Temperature (T), Volume (V), and Number of Particles (n)
1.
2.
3.
4.
Faster particles expand
Faster, more & harder collisions
Increase Increase
Slower particles contract
slower, less & softer collisions
Decrease Decrease
More mass, more kinetic energy
More particles, more frequency of hits
Increase Increase
Less mass, less kinetic energy
Less particles, less frequency of hits
decrease Decreas
es
KE =1/2 m • v2
KE =1/2 m • v2
KE =1/2 m • v2
KE =1/2 m • v2
KE =1/2 m • v2
The Relationship Between P, V, T, n
1. Which graph represents the relationship between the pressure
of a gas vs. its volume?
2. Which graph represents the relationship between the pressure
of a gas vs. the absolute temperature?
3. Which graph represents the relationship between the pressure
of a gas vs. the Celsius temperature?
4. Which graph represents the relationship between the pressure
of a gas vs. the number of particles?
7. Which graph shows a constant pressure vs. volume
8. Which graph shows constant 0°C vs. increasing volume
1 -7, pressure is on the y axis, #8 temperature is on y axis
A
B
D
B C
C
Molecular Kinetic Theory of Gases 4. Define Kinetic Energy (KE) Energy due to motion. Mathematically KE = ½ mv2 m = mass, v= velocity
5.State the kinetic molecular theory that accounts for the behavior of gases.
Particles of a gas: a) *are in constant motion, b) they do not “lose energy”; they maintain their speed c) do not stick to other particles. d) *The speed of the particles is related to their temperature. e) *The pressure of a gas is related to the frequency (how
often) and how hard the particles hit the sides of the container in which they are enclosed.
* Also true for liquids and solids not at temperature of absolute 0°
Energy Transfer • Describe the ways that energy is transferred
between the system and the surroundings.
These are:
– Heating – transfer of energy through the
collisions of particles
– Working – transfer of energy when macroscopic
objects exert forces on each other
– Radiating – transfer of energy by the emission or
absorption of light
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