Transcript Chemistry Basics Power Point

Where does the energy we use come
from?
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Electricity
Biomass Energy - energy from plants
Geothermal Energy
Fossil Fuels - Coal, Oil and Natural Gas
Hydro Power and Ocean Energy
Nuclear Energy
Solar Energy
Wind Energy
Transportation Energy
Source: U.S. Energy Information Administration, Office of Coal, Nuclear, Electric and Alternate Fuels
Courtesy of World Resources Institute, 10 G Street, NE (Suite 800), Washington, DC 20002
Courtesy of Uranium Information Center Ltd Energy for the World - Why Uranium?
http://www.eia.doe.gov/oiaf/ieo/highlights.html
http://www.eia.doe.gov/oiaf/ieo/highlights.html
Courtesy of Economic Energy Report by Michael Hodges
PENNSYLVANIA FACTS
• Pennsylvania ranks second in the nation in nuclear power generating
capacity
– 5 operating power plants that provide 1/3 of the electricity needs of the
state
• PA is a major coal producing state, selling ½ of its coal output to other
states
• PA is the leading petroleum refining state in the Northeast
• PA’s electricity production exceeds state demands
• PA is among the largest users of municipal solid waste and landfill gas
for electricity generation
• PA produces substantial hydroelectric power
• In December 2004, PA adopted an alternative energy portfolio standard
that requires electricity companies and generators to supply 18.5% of
PA’s electricity from alternative energy sources by 2020.
With your assigned group members discuss solutions to the
following problem. Come to agreement as a group on a
solution, and choose one member that will present your
solution at the end of class.
Problem: What can be done to meet the
United States’ ever-growing energy demands while
improving the quality of life of today’s society
without sacrificing the quality of life of future
generations?
Law of
Conservation
of Energy
Energy cannot
be created nor
destroyed!
Type of Energy
Kinetic
Examples
Potential
Ball held above ground,
water before a dam
Radiant
Light, Microwaves, Xrays, Gamma waves
Electrical
Electricity, static cling,
lightning
Magnetic
Mechanical
Thermal
Nuclear
Magnets, compasses
Chemical
Gasoline, oil, batteries,
food
Spring
Stretched rubber band,
bungee cord, spring scale
Sound, Wind, Spinning
Wheel
Pistons in a car engine
Heat
Nuclear fission, nuclear
fusion, heavy water
Law of Conservation of Energy
Energy cannot be created nor destroyed!
Draw your
final sketch
today.
Label all 10
forms of
energy
associated
with your
machine.
Webster's Dictionary definition of "rube goldberg”: Accomplishing by extremely
complex, roundabout means what seemingly could be done simply.
Objective:
Make a drawing of a Rube Goldberg device of your own
creation which includes examples of each of the 10 basic
types of energy and 10 different energy changes.
10 energies - these should be clearly labeled and numbered
in blue next to where the energy occurs in the drawing.
10 different energy changes - arrows should be drawn
connecting each energy in the drawing to the next in red to
show how one type of energy is changing into another.
Calorie
• Always refers to the energy in food
• A measure of how much potential energy that food
possesses
• 1 Calorie = 1 kilocalorie = 1000 calories
• Body burns calories through metabolic processes
• Enzymes break carbohydrates into glucose and other
sugars, fats into glycerol and fatty acids and proteins
into amino acids
Caloric Breakdown
• 1 gram carbohydrates = 4 Calories
• 1 gram protein = 4 Calories
• 1 gram fat = 9 Calories
Underweight <5%, Healthy 5-85%, Risk of Overweight 85-95%, Overweight >95%
The Body’s Caloric Needs
• 2,000 Calories is an average body’s need
• Height, weight, gender, age and activity
level all affect a person’s caloric needs
• To calculate your body’s needs add together
– basal metabolic rate
– physical activity
– thermic effect of food
BMR--Basal Metabolic Rate
• Accounts for about 60 to 70 percent of calories burned in a
day
• Includes the energy required to keep the heart beating, the
lungs breathing, the kidneys functioning and the body
temperature stabilized
 Adult male: 66 + (6.3 x body weight in lbs.) + (12.9 x
height in inches) - (6.8 x age in years)
 Adult female: 655 + (4.3 x weight in lbs.) + (4.7 x height
in inches) - (4.7 x age in years)
 Ms. Wack’s BMR = 1366.4
Physical Activity
Sedentary Activities Energy Costs in Cals/Hour
Lying down or sleeping - 90
Sitting quietly - 84
Sitting and writing, card playing, etc. - 114
Moderate Activities (150-350 cal/hr)
Bicycling (5 mph) - 174
Light housework, cleaning, etc - 246
Bicycling (6 mph) - 240
Swimming (crawl, 20 yards/min) - 288
Dancing (Ballroom) - 210
Gardening - 323
Golf (twosome, carrying clubs) - 324
Walking (2 mph) - 198 to 240
Walking (4 1/2 mph) - 440
Walking (3 mph) - 320
Thermic Effect of Food
• The amount of energy your body uses to
digest the food you eat
• Multiply the number of calories you eat in a
day by 10% (0.10)
Food
American Cheese
Apple
Apple Juice
Bacon
Bologna
Caesar Salad
Carrot, fresh
Cheesecake, Plain
Cola
French Fries
Frozen Waffles
Hamburger
Hamburger roll
Macaroni and Cheese
Milk
Pizza, Cheese
Potato Chips
Pretzels
Serving Size
1 slice
1 medium
8 fluid ounces
2 slices
1 ounce
10 oz. w/ dressing
1 medium
1/4 of 19 oz cake
8 oz
10 strips
2 waffles
4 oz. Patty
1 roll
7.5 ounces
8 ounces
1 slice
1 ounce
1 ounce
Calories
70
80
120
80
90
520
35
330
100
160
220
445
130
260
160
290
150
110
Use the handouts on your table to determine the # of
calories you eat in an average day (estimate it). Then use
the calculations from yesterday and the information below
to determine whether you should be losing, gaining or
maintaining weight. Write your answers on your handout
from yesterday.
Effects of Calorie Intake
• An accumulation of 3500 extra Calories is stored by your
body as 1 pound of fat
• Lose 1 pound of fat when you burn 3500 more calories
than you eat
• Burn what you eat to maintain your weight
• Body burns an increased # of calories for 2 hours after
exercise
What happens when you don’t
get the Calories you need?
• Body initially responds with weight loss by
breaking down fat
• After a few weeks body senses starvation and your
metabolism will decrease so less overall energy is
needed
– Body will look for other sources of fuel & will begin
breaking down muscle resulting in loss of lean muscle
mass (if already underweight can result in loss of tissue
surrounding internal organs, including the heart).
• Symptoms: Fatigue, diarrhea, inability to stay
warm, irritability, weakened immune system,
calories
• A unit of energy
• The quantity of heat needed to raise the
temperature of 1 g of pure water 1°C
Calorie
• Always refers to the energy in food
• A measure of how much potential energy that food
possesses
• 1 Calorie = 1 kilocalorie = 1000 calories
• Body burns calories through metabolic processes
• Enzymes break carbohydrates into glucose and other
sugars, fats into glycerol and fatty acids and proteins
into amino acids
Joule
• The SI unit of energy
• the symbol for Joule is J
• 1 J = 0.2390 cal
• 4.184 J = 1 cal
Energy Conversions
1 Calorie = 1000 calories
4.184 J = 1 calorie
Temperature
• Measured with:
Kelvin Scale: The S.I. Scale
Fahrenheit Scale: An
•Based on absolute zero.
arbitrary scale created by
Celsius Scale: Based on
Gabriel Fahrenheit.
the freezing and boiling
points Zero:
of water.
Absolute
The point at
which the motion of particles
C
(F–9/5)
32)+ 
F =
= (C
325/9
of matter (their kinetic energy)
ceases. C = K – 273
K = C + 273
Properties & Changes of
Matter
Matter
Anything that takes up space and has mass
Can be classified as solid, liquid, gas or plasma
Is it matter?
What is not matter?
ENERGY, HEAT, LIGHT,
ELECTROMAGNETIC WAVES,
MAGNETIC FIELDS, IDEAS, ETC.
Properties of Matter
Describe the characteristics and behavior
of matter, including the changes that
matter undergoes
Observing Matter
 Macroscopic Observations: Observations made with the
5 senses
 Microscopic Observations: Observations made with a
microscope
 Submicroscopic Observations: Observations of
substances so small they cannot even be seen with a
microscope
Macroscopic
Microscopic
Submicroscopic
 Qualitative
Observation:
Describes the
properties of a
substance
 Quantitative
Observation:
An observation
that involves a
numerical
value.
Physical Properties
What are the physical properties
represented in the image above?
Mass
Units: grams or kilograms
Measured with: Triple Beam Balance
VOLUME
SI Unit: cm3 or m3
Measured with: a
meterstick or a metric
ruler
Common Unit: mL or L
Measured with: a
graduated cylinder
If the same amount of
liquid is found in both of
the above containers—
which has more volume?
States of Matter
• Depends on:
• Solid:
• Liquid:
• Gas:
PLASMA
The most common form of matter
Free electrons and ions of an element.
Energy is needed to
strip atoms of their
electrons.
Plasmas can be
steered and
controlled by
magnetic and
electric fields.
PLASMA TV’S
•Xenon and Neon in each cell
•Intersecting electrodes charged causing
electric current through the gas in that cell
•Electric current = rapidly flowing charged
particles causing the release of UV photons
•Photons interact with the phosphor
coating giving off colored light
Because each cell is lit individually, the image
is bright and looks good from almost any angle.
Chemical Properties
Chemical Reaction: A Chemical Change
• After a chemical reaction: The original substance
no longer has the same identity
• Chemical reactions can be used to:
Is it a chemical reaction?
Law of Conservation of Matter
•Matter cannot be created nor destroyed in a
chemical reaction.
•Developed by: Antoine Lavoisier
•Mathematically:
Mass of the reactants = Mass of the products
(starting materials)
(ending materials)
PURE SUBSTANCE

Matter with the same fixed composition
and properties
– First Type of Pure Substance
 Element
– The Periodic Table: A chart that lists the chemical name
and chemical symbol for each element
– Chemical Symbol: A shorthand abbreviation for the
name of an element
– You can tell a substance is an element because it is on
the periodic table
-Can you separate an element? No
Aluminum = ___
Gold = ____ Tin = ____
PURE SUBSTANCE

Matter with the same fixed composition and properties
– Second Type of Pure Substance
 Compound
– Chemical Formula: A combination of chemical
symbols that show what elements make up a
compound and the number of atoms of each
element
 Subscript: A number written to the lower
right of an element symbol to indicate the
number of atoms of that
– How do you know if a substance is a
compound? If it is 1 thing only—and it is not
on the periodic table.
– Can you separate a compound? Yes—by
chemically decomposing it.
NaH2CO3
Mg(OH)2
Decomposing a Compound
Electrolysis
– “To tear apart with electricity”
– The process in which electrical energy causes
a non-spontaneous chemical reaction to occur
 May break a compound apart into its elements
 Electrolysis of PbBr2 & ZnCl2
 Electrolysis of Water
MIXTURES
Two or more elements physically combined.
How can you tell something is a mixture?
It can be physically separated into its parts.
Heterogeneous Mixtures
• The prefix “hetero” means “different”
• A mixture with different compositions throughout
• You can see each phase (part) of the mixture
Homogeneous Mixtures
• The prefix “homo-” means “the same”
• A mixture that is the same throughout
• You cannot see the phases (parts) of
the mixture.
ALLOY
NAME OF ALLOY
% MAKE UP
Stainless Steel
73-79% Fe
14-18% Cr
7-9% Ni
Sterling Silver
92.5% Ag
7.5% Cu
18-karat white gold
75% Au
12.5% Ag
12.5% Cu
14 karat gold
58% Au
14-28% Ag
14-28% Cu
EXAMPLE
Solutions
• Solute: The substance being dissolved in a
solution
• Solvent: The substance that dissolves the solute
• Aqueous Solution: A solution in which water is
the solvent
HETEROGENEOUS
OR
HOMOGENEOUS?
What is the solute?
What is the solvent?
82% Fe
18% Cr
Methods to Separate Mixtures
• Filtration: Separates a solid from a liquid
Separating…
• Magnet: Separates Fe, Co, or Ni
Separating…
• Distillation: Separates two or more liquids
with different boiling points.
Separating…
• Crystallization: Separates crystalline solids
from a saturated liquid
Separating…
• Chromatography: Separates different types
of liquids