Transcript Matter & Energy

BELL RINGER
Explain, in terms of
particles and energy,
the different states of
matter.
MATTER & ENERGY
MATTER - anything that has
mass and volume
ENERGY -
the ability to
do work
Matter
Can it be physically separated?
YES
Mixture
Pure Substance
Is the composition
uniform?
Yes
Homogeneous
Mixture
NO
No
Heterogeneous
Mixture
Can it be chemically
decomposed?
Yes
Compound
No
Element
BELL RINGER
2. Looking at the graph on the
right, characterize each
variable as independent or
dependent.
Temperature (ºC)
1.What does C6H12O6 (aq) mean?
Time (sec)
Examples
Graphite
- element
Pepper
- heterogeneous
Sugar(sucrose)- compound
Paint
 Milk
- mixture
-
Homogeneous
mixture
Ne
SO3
N2
Homogeneous
Mixture
Practice
Practice
Physical Properties
• Are constants about the substance
• Can use our senses to observe them
•
Extensive
depends on how much material you have
Intensive
A constant, does not matter how much
Physical Changes  does not alter the substance
–
Can be reversed
Chemical Properties
 Properties substances adhere
to when they REACT with
other substances
 Chemical Changes –
 ID by color change, bubbles, heat Δ
 Examples
 rust, burning a log, ice pack
ID the following as being intensive, extensive, or
chemical properties
__________ The mass of copper wire is 325g.
__________ The boiling point of ethanol is 77.0 °C
__________ Baking soda reacts with vinegar to make CO2(g)
__________ The density of mercury is 13.6 g/ml.
__________ The solubility of sodium chloride in water is 40g/100 ml of water.
Physical vs. Chemical
 Chemical Changes Mythbusters
Mentos
Rocket
Matter
Can it be physically separated?
YES
Pure Substance
Mixture
Is the composition
uniform?
Yes
Homogeneous
Mixture
NO
No
Heterogeneous
Mixture
Can it be chemically
decomposed?
Yes
Compound
No
Element
BELL RINGER
NO, you don’t have to write down the chart
Mixture 1 (100 ml)
Mixture 2 (100 ml)
Composition
NaCl in H2O
Fe fillings in H2O
Observations
• Colorless liquid
• No visible solid on
the beaker bottom
• Colorless liquid
• Black solid on bottom of
beaker
Other Data
• Mass of NaCl(s)
dissolved = 2.9 g
• Mass of Fe(s) = 15.9g
• Density of Fe(s) = 7.87g/cm3
1. Classify each type of mixture.
2. Determine the volume of Fe
fillings used to produce mixture 2.
Made of two or more separate compounds
In chemistry, this is usually a solid and a liquid
A. Types of mixtures
1. Suspension Heterogeneous
Largest particles Over 1 µm
If left alone, particles will settle
Can also filter the mixture to remove particles
2. Colloid
Heterogeneous
Smaller particles, may be invisible
Between 0.001 - 1 µm
Mixture is not transparent
Particles do not settle. Cannot be filtered
3. Solution Homogeneous
Smallest particles Under 0.001 µm
Invisible - solution appears transparent
Particles cannot be filtered Must distill the solution to remove solids
B. Solutions
1. Parts
Solute - Smaller of the two materials – usually solid
Solvent - Larger quantity of the two – usually water or liquid
Solutions are labeled (aq)
CaCl2(aq) Calcium chloride dissolved in water
2. Solubility
How much solute can go into a solvent
Tyndall Effect
• Used to identify a colloidal solution or a
suspension, light is reflected by the dissolved
particles
• Solutions particles are too small
Tyndall Effect
Matter
Can it be physically separated?
YES
Pure Substance
Mixture
Is the composition
uniform?
Yes
Homogeneous
Mixture
solutions
NO
No
Heterogeneous
Mixture
suspensions
colloids
Can it be chemically
decomposed?
Yes
Compound
No
Element
STATES OF MATTER
•Solids
•Liquids
•Gases
•Plasma
STATES OF MATTER
Atom Movement
What happens to an atom when
the kinetic energy changes?
Click Here
Vibrational
Rotational
- particles are constantly vibrating
- about an axis, they flip over end to end
Translational - particles move from place to place
STATES OF MATTER
SOLIDS -
•very low KE - particles can
vibrate but not move
•fixed shape & volume
•Do Not conform to the
container shape
•Vibrate only
STATES OF MATTER
•Crystalline solid –
arranged in a
specific pattern
such as diamonds,
salt, or ice
•Amorphous solid –
no molecular order
as found in
charcoal, plastics
and glass
STATES OF MATTER
LIQUIDS •low KE
- particles can move around but are still
close together
•variable shape but packed closely
together
•fixed volume
•(incompressible)
• Vibrate & Rotate
STATES OF MATTER
GASES •high KE -
particles can separate and move
throughout the container
•Variable shape & volume
•Fluid and Compressible
• Vibrate, Rotate, Translate
STATES OF MATTER
PLASMA -
•Very high KE - particles
collide with enough energy to
break into charged particles
(+/-)
•variable shape & volume
•Stars, fluorescent light bulbs
STATES OF MATTER
Animation
Very good display of the
differences in states of matter
HEAT vs. Temperature
Temperature
- the measure of an object’s average kinetic energy
- the more an object moves, the higher the temperature
Heat
- flow of energy from a higher temperature object to a lower
temperature object
Heat Transfer
Endothermic Heat absorbed during a reaction
Exothermic Heat given off during a reaction
Think
Temperature (KE)
Using the following graph, draw a line, representing the
temperature of a substance as it is heated constantly starting
as a solid all the way through to a gas.
Time
BELL RINGER
Which of the following phase
changes are exothermic?
Just right down the correct choice!
1. CO2(s) + heat  CO2(g)
2. NH3(g)  NH3(l) + heat
3. Cu(s) + heat  Cu(l)
4. Hg(l) + heat  Hg(g)
Temperature (KE)
Heating Curve
 KE
PHASE 
 KE
PHASE 
 KE
Time
Temperature (KE)
Heating Curve
q=mHv
q=mc T
q=mc T
q=mHf
m = mass
c = specific heat [4.18]
q=mc T
q = heat loss/gain
Time
Heat Energy Problems
How much heat energy, in joules, is absorbed
by 24.8 grams of water when it is heated from
21.2ºC to 28.3 ºC?
Get the formula from Reference Tables
q = mcΔT
q = 24.8g (4.18J/g•ºC) 7.1ºC
q = 736 J
q = 740J
Heat Energy Problems
How much heat energy is absorbed when
11.3g of ice melts to form liquid water at the
same temperature?
Get the formula from Reference Tables
q = mHf
q = (11.3 g) (334J/g)
q = 3774.2 J
q = 3770 J
Heat Energy Problems
If it takes 273.3 J of energy to condense 19.2 g
of a substance, what is the heat of vaporization
of a substance
Get the formula from Reference Tables
q = mHv
273.3J = (19.2 g) (x)
Hv = 14.2 J/g
BELL RINGER
The temperature of a piece of copper with a
mass of 95.4 g increases from 25.0°C to
48.0°C when the metal absorbs 849 J of heat.
What is the specific heat of copper?
q = mcΔT
849J = (95.4 g) (c) (23.0 K )
c = 0.387 J/g•K
Cooling Curve Lab
Heat Energy Problems
How much heat is absorbed when 70.00 g of
water is completely vaporized at its boiling
point?
Get the formula from Reference Tables
q = mHv
q = (70.0 g) (2260J/g)
q = 158200 J
BELL RINGER
Just sketch the
graph!
Temperature (C)
Cooling Curve for Lauric Acid
80
A
60
B
C
What
40
20
D
Lauric Acid is
starting as a
liquid
0
0
2
4
6
8
10
Time (min)
Which line segment represents a phase change only?
What is the melting point of lauric acid?
At which point do the particles of lauric acid have the
highest kinetic energy?
What phase change occurs during this 10-minute graph?
Quiz
Heat Problems
Remember: The
energy to melt the
ice only comes from
the warm water!!!!!!!!!
BELL RINGER
If it takes 22.0 kj of energy
to change 43.2 g of a
substance to a liquid, what
is its heat of fusion?
509 Joules/gram
Separation Techniques
Since the components of a mixture are different
substances, with at least some physical properties that
are unique to each substance, mixtures can be
separated by physical means into their components by
techniques such as …
Filtration
Distillation
Decanting
Chromatography
And many others
Filtration
Is the process of
removing ‘straining’
a solid, precipitate,
from a liquid using
a porous paper
Mixture of
solid and
liquid
Stirring
rod
Funnel
Filter paper
traps solid
Filtrate (liquid
component
of the mixture)
Filtration
• For separation of substances in
different phases
•Ex – Air filters, coffee filters, fuel
filters
• Decanting
•Immiscible liquids – separation
by differing densities  use a
separatory funnel
decanting
•Pouring a liquid off of a solid
decanting
• carefully pouring a solution
from a container, leaving the
precipitate in the bottom of
the container.
•Precipitate – solid formed
in a solution during a
chemical reaction
chromatography
•Separation of a mixture based upon bonding
preferences or size of molecules
•Tie-dye
•Pen ink
•Chlorophyll
•Paternity testing
Separation of Mixtures
Chromatography
• separation of
substances based on
their attraction for
substances not in the
mixture
•Gas
•Paper
Distillation
•The separation of a mixture based upon boiling
point differences.
•The substance with the lower boiling point will
vaporize and re-condense as a purified substance
•Used to purify liquids
•Distilled water
Cooling
water
out
Cooling
water
in
Run hose
into sink
Connect hose
to cold water
tap
Distillation
Cooling
water
out
Run hose
into sink
Cooling
water
in
Connect hose
to cold water
tap
Distillation
• separation of
substances by their
boiling point
•Miscible liquids
• Solutions
• Volatility – measure of the
speed at which a
substance evaporates
Fractional Distillation
Distillation
SHAKE
TEST
What would be the temperature change if 3.00g of water absorbed
29.2 J of energy?
At 1.00 atm of pressure, 25.0 g of a compound at its normal
boiling point are converted to a gas by the addition of 34400.J
What is the heat of vaporization of this substance?
If 122.3 J are added to 32.8 g of water at 30.0°C, what will be the
final temperature of water?
23422 J of energy was used to change the temperature of 162.8g
substance from 13.2°C to 19.4°. What is the specific heat of the
substance?
A 14.3g sample of liquid water at 100.0°C is cooled to solid water
at 0.0°C. How much energy was released?
BELL RINGER
Gas
Boiling Point
Melting Point
Solubility in
Water
Nitrogen
-196ºC
-210ºC
Insoluble
Hydrogen
-252ºC
-259ºC
Insoluble
Ammonia
-33ºC
-78ºC
Soluble
Describe how to separate ammonia
from hydrogen and nitrogen.
Law of Conservation of Energy
=energy is not created nor destroyed
REMEMBER: Heat energy always
travels from the higher temperature
to the lower temperature until both
temperatures are the same.
Temperature Scales
Temperature
• measures how fast
an object’s molecules
are moving = KE
•Different scales have
been developed
•Only need two fixed
points to develop your
own scale
Temperature Conversions
On Reference Tables
K = °C + 273
A 1.0 °C change = 1.0K change
Some Test Topics:
Matter Classification
PE vs. KE (how measured, when changing)
Separation Techniques
Temperature Conversions
Heat Formulas
Phase Changes (aqueous)
Heating/Cooling Curves - interpret
BELL RINGER
How can you tell if a
physical change has
occurred?
Separation by Chromatography
sample
mixture
a chromatographic column
stationary phase
mobile phase
selectively absorbs sweeps sample
components
down column
http://antoine.frostburg.edu/chem/senese/101/matter/slides/sld006.htm
detector
Separation by Chromatography
sample
mixture
a chromatographic column
stationary phase
mobile phase
selectively absorbs sweeps sample
components
down column
http://antoine.frostburg.edu/chem/senese/101/matter/slides/sld006.htm
detector
_________ Curve
Temperature (KE)
Label Everything!
Time
Pure Substances

Element
–contain only ONE kind of atom
–Ex - copper
gold
Pure Substances
• COMPOUND
– composed of 2 or more
elements in a fixed ratio
–new properties different from
individual elements
Na
NaCl
Cl2
The compound has completely
different properties than the element
Temp (C)
BELL RINGER
120
100
80
60
D
E
40
20
B
0
-20
C
A
0
200
400
600
800
1000
Heat (Joules)
0
80
240
320
740
Heat (Joules)
The graph shows the heating curve of 2.0 gram of a
solid as it is heated at a constant rate, starting below its
melting point. What is the heat of vaporization and
along which line on the graph is it measured?
Heat Problems
Problem #3 back of sheet
from last class
100 ° C
0°C
Analysis By Separation Lab
X 100%
Analysis By Separation Lab
Write-Up
1. Procedure – replaces the purpose
2. Safety
3. Data: ALL Data and calculations
4. Questions – answered in complete
sentences
5. Summary
Exam
BELL RINGER
A student has a flask containing
two immiscible liquids. One of
the liquids is a solution of a solid
in water. Describe how you
would separate the mixture into
its three separate components?
BELL RINGER
If it S
Specific Heat Lab
BELL RINGER
How many phases
of matter exist?
What are they?
BELL RINGER
How can you tell if a
physical change has
occurred?
BELL RINGER
Temperature (C)
120
100
80
60
40
Just sketch
the graph!
20
0
0
10
20
30
40
Time (min)
1. What is the freezing point of the substance
in the above graph?
2. In a box on your paper, draw at least 9
particles (•) of the substance during the
first 3 minutes of heating.
Precision and Accuracy