Unit 2 Matter
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Transcript of Unit 2 Matter
Unit 2 Matter
Chem 1
Be Seated
CHEMISTRY
Agenda 10/4
1. Panther Drill 42. Notes (Properties and States of Matter)3. PD Redux, If I knew then what I know now4. WS Sci Notebook Sec 3.15. Close/Exit Ticket
Panther Drill 4
Identify the state of matter of the following: (IE is it Liquid ect) O2
Water IceWater Vapor Inside Florescent Lights Blood Jell-OThe Sun Mostly Plasma, Some Gas
Liquid
Liquid
Solid
Solid
Gas
Gas
Plasma
SubstancesA substance is matter that has definite composition
and properties.
i.e. Table salt (NaCl) always has the same make-up and properties no matter if you put it on your popcorn in Lake City, Murrells Inlet, or Lake City Colorado.
Whereas salt water found in the pacific ocean is different than salt water found in the arctic ocean.
COMPOSITION OF MATTERWhat is MATTER?
Anything that Takes up Space and Has Mass.
What are the States of Matter?Solid, Liquid, Gas, Plasma
1) Solid: Definite volume and definite shape (Glass)
2) Liquid:Definite volume indefinite shape (Water)
Solids and LiquidIn a solid. all molecules vibrate
and forces of attraction hold them in place.
In a liquid the molecules have partially overcome the forces of attraction and still partially in contact
COMPOSITION OF MATTER Gas:
Indefinite volume, indefinite shape.IE Car Exhaust
Plasma:High temperature physical state, made
up of free electrons and ions of the element IE Florescent Lights, Mushroom Cloud, the northern lights, and Plasma TVs.
Gas and PlasmaMolecules have completely
over come attractive forces, any contact is random.
Movement is extremely fast and electrons are striped away from the molecules.
Characteristics of States of Matter
http://www.nasa.gov/images/content/147515main_phases_large.jpg
PropertiesExtensive properties: properties that depend
on how much of matter is present.i.e. Volume and Mass
Intensive properties: does not depend on how much matter is presenti.e.: density and boiling point
Physical Properties
Physical Properties: something that can be changed in a substance w/o changing its identity. i.e.: Melting Ice
Cutting a 2x4 in half Boiling
Chemical Properties MatterChemical Properties: changes that result in a
substance being changed into new substances.i.e.: Burning charcoal = carbon ash and O2 & CO2
Iron Rusting
** A physical or chemical change requires energy to be added to what ever is changing (aka the system)Energy can be heat or light other forms
Shoulder Partners Answer and check ea. other answers
Mushroom Cloud S,L,G,PShampoo S,L,G,PJell-o S,L,G,P
Burning Gas Physical or ChemicalBaking Cookies Physical or ChemicalMaxing Salt water Physical or Chemical
Odor Extensive or IntensiveWeight Extensive or IntensiveColor Extensive or Intensive
Compare and Contrast Extensive and Intensive properties
Show it to me before you leave
Before you pack up
10/51. PD 52. Notes 3. Example Conservation of Mass4. Do practice problems w/ partners5. Exit Problem
Modified Seats 3rd Period
Spud
Ashley
Amber
Wade
Go to your seats and Panther Drill will start at bell
Gaskins
Porchea
Josh
Cordrick
Stukes
YessieGalloway
Pace
Justice
Belinda
Kyianna Terrance Breanna
Modified Seating 6th PeriodSade’ Jasmine
JustinWhitney
DemondTerica
Jaron
Willie
Nasia
Tyiesha
ShekiaTykosha
SteveReggie
Diamond
Keshon
Quay
JamikaRayneesha
Kayla
Dominque
Panther Drill #5Think about what you know about
nature, tell me about how the physical phase change of water, effects the natural world.
Kinds Physical Changes Freezing is the change of state from a liquid to a solid. Melting is the change of state from a solid to a liquid. Vaporization is the change of state from a liquid to a
gas. Condensation is the change of state from a gas to a
liquid. Sublimation is the change of state from a solid directly
into a gas. Deposition is the change of state from a gas directly into
a solid.
Example
More energy in the system
Less energy in
the system
State Changes and the Environment
Chemical ReactionsIn a chemical reaction there are the reactants and
the products. Reactants: what you start with Products: what you end with
99.08g Fe + 55.92 g O2 155g Fe2O3(Rust)
Reactants ProductsWhat is the mass of the Fe and the O?What is the mass of the Fe2O3?
99.08g + 55.92g
155g
Law of Conservation of Mass
“Matter can’t be created or destroyed in a chemical reaction, it is conserved”
That means the mass of the reactants = the mass of the products.
Mass reactants = Mass products
Get in your pairings and work on problems
Partners 1st PeriodBrad & LaTonyaMary & QualishaQuanisha & HowardHank & Brenton Jess & AbriaRaven & CodySam and DevonteCassidy and DevontaTrevon’ & Drequan
Partners 3rd PeriodJosh & CordrickKyiana & BelindaBreanna & TerranceJustice & YessieGalloway & CadejahGaskins and SpudBrandon and PorscheaAshley, Amber, & Clarence
Partners 6th PeriodJaron & Willie Steve &
DiamondJamika & Dominique Tiesha, Keshon &Shekia Reggie, & Kayla Nasia & TykoshaJustin & QuaySade’ & WhitneyJasmine & DemondRayneesha & Terica
Partner A show partner B how to do Problem #1 Then Reverse roles
1. When 245 grams of KClO3 are heated, the KClO3 breaks down into 78 grams of potassium, 71 grams of chlorine and some oxygen gas. What is the mass of oxygen gas formed?
2. You have 729 g of NaOH (Sodium Hydroxide) is broken down into its parts. What resulted was 459 g of Na, 127 g of Oxygen, and how many grams of Hydrogen?
Do number 6,7&8 from pp 78 in your text by
yourselves, and show it to me, before you pack-up
Agenda 10/6
1. PD #62. Notes/Discussion (Mixtures/Pure
Substances/Separation) 3. PD Redux4. Exit Assignment5. Lab Thurs. Reminder
Panther Drill #6Identify the following items (NOT as solid liquid
or gas) but as mixtures or pure substances.AluminumTable SaltWaterStainless Steel Kool AidCarbon
Mixture
MixtureMixture
Pure
Pure
Pure
DRESS FOR LAB TOMORROW THURSDAY 10/7
Classification of MatterMatter is classified as either a MIXTURE or a PURE
SUBSTANCE.1) Pure Substances: is homogeneous and has a fixed
composition. Every sample has the exact same propertiesIE all pure water boils at 100C and freezes at 0C
Every sample has the exact same composition IE all pure water has 11.2% H and 88.8% O2
Classification of Matter2 kinds of pure substances:Compounds and Elements
Elements: a pure substances that can not be broken down into simpler parts IE Carbon
Compound: a substance that can be broken in to simpler substances. IE WATER - H and O
Classification of Matter2) Mixture: blend of 2 or more kinds of matter,
where each different type of matter keeps its own identity or properties. Mixtures can be broken down into their original parts.
2 kinds of mixtures:Homogeneous: these have uniform composition always in a single phase, blended uniformly.
oSteel (a mix of carbon and iron) oMilk oMayonnaiseoSolutions
Classification of MatterMixtures Cont.
Heterogeneous: these are not uniform, their composition changes from sample to sample, they are not blended smoothly.
• Buttermilk• Fresh squeezed orange juice• Homemade mashed potatoes• Pond water
Classification of Matter
Separating MixturesFiltration: using a filter to separate the a
heterogeneous mixture of solid and liquidDistillation: using different boiling points of
substances in a homogeneous mixture to separate it
Separating MixturesCrystallization: when pure solid forms from a
liquid solution containing as much solid as can be held be the liquid (super saturated). Solid is then formed as the liquid evaporates (Think making rock candy.)
Sublimation: separation of solids and gas w/o going through liquid state
Separating Mixtures
Chromatography: separate the components of a mixture (liquid or gas) by allowing it to move across another material (i.e. paper). The components separate because the move across the paper at different rates.
If I only knew then what I know now…
Identify the following items as mixtures ore pure substances.
OxygenSugarSugarGator AidPizzaWater
Mixture
MixtureMixture
Pure
Pure
Pure
Text assignment pp 83 #16,18
Due before you leave
Get into you lab Groups
Start Pre-Lab questions and assign jobs to members.
1. Equipment Person2. Experimenter3. Recorder4. Leader/Clean up5. If 5 in group then divide leader and cleanup
Thursday 10/7
Agenda1. Panther Drill 72. Lab “”3. Closure
Panther Drill #7
Get into your lab groups and see who in your group is in violation of Lab Safety Rules.
Friday 10/8 Early Dismissal
Agenda1. Panther Drill 8 Turn in for quiz2. Finish Analysis and Conclusions for lab from
10/7
MONDAY Agenda 10/11
1. PD 8 quiz2. Notes/Discussion
(Elements/Compounds/Periodic Table basics) (10 min)
3. WS 3.4 (10 min)4. Trading Card Game Elements/Compounds (10
Min) 5. Exit Ticket 5 min
Panther Drill #8
Can you explain in your own words….?How many...?Can you distinguish between ….?Can you name the...?Can you tell why...?Find the meaning of...?
Write out 2 sample quiz questions based on last weeks material that start with:
1Write out 1 sample quiz questions based on last weeks material that start with:
Can you design a ... to ...?Compare and contrast….?Explain the differences between…?Rank the following based on…..
2
QUIZCHOOSE 4 TO ANSWER
1. Compare and contrast a physical and chemical change.
2. Explain the best way to separate the pulp from fresh squeezed OJ, and the best way to separate salt water into its components.
3. Explain the law of conservation of mass.4. Compare the molecule structure of the all 4
states of matter.5. List and explain 5 of the 6 physical changes
of matter.
Elements
Elements are pure substances that can not be broken down into simpler substances by physical or chemical means. Oxygen, Carbon, Boron ect.
Abbreviated by 1,2,or 3 letter abbreviation 1st letter always capitalized. O, Al, Zn, Uus (Ununseptium)
91 NATURALLY occurring elements on the earth.
CompoundsCompounds are a combination of 2 or more different
elements that have combined or bonded chemically.
Most of the matter in the universe is compounds.There are approx 10 million known compounds with
more discovered or created all the time.
List some compounds that you encounter every day life:
GasolineC8H18
Baking soda CHNa03
Milk of magnesium (Medicine) Mg(OH2)
Cream of tartar (Used in cooking)KC4H5O6
Periodic TableThe periodic table is table that organizes all known
elements into horizontal rows and vertical columns based on their properties.
The modern periodic table is based mainly on the work of Russian Scientist Dmitri Mendeleev.
Mendeleev’s predictions of blank yet to be discovered elements and where they would fit in the table were pretty much right on.
We will do much more work with the periodic table later in the semester.
Mendeleev’s Periodic Table
Modern Periodic Table
Tuesday Agenda
1. PD 8 How do compounds made of the same elements differ, and what does that mean to their properties. (5min)
2. WS 3.4 (Notebook) 10 (min)3. Notes/Discussion Law of Definite proportions (10 min)4. Modeling Example Law of Definite proportion problems
(10 min)5. Independent practice problems (20 Min) pp78 #s 20-236. Exit ticket (5 min)
Panther Drill 9
Answer the following question:
How do compounds, made of the same elements differ, and what does that mean to their properties?
IE H2O and H2O2
WS 3.4
Take the first 10-12 min to start WS # 3.4, us section 3.4 in the Chem Text to complete it and then put it in the Classwork Section of your notebook.
Law of Definite ProportionIndividual Compounds are named and defined by the
number and ratio of the elements they are made of.
WHAT IS A RATIO? Relationship between two of the same kind of numbers. The relationships in this case of the subscripts or small #s below each elements, which is the # of atoms of that element in the compound.
Law of Definite Proportion 2This is so important that it is stated in a law of
moderns Chemistry, The Law of Definite Proportion.
This law says that in a compound the elements are always present in the same proportion.
IE: H20 There are always 2 Hs for every 1 O in water.
Formula you need to know how to use
Percent mass or mass percent =
Mass of the element x100Mass of the compound …
Mass PercentA 25 gram sample of water contains 2.80 grams
of hydrogen.What is the mass % of hydrogen?
2.80g/25g X 100 =11.2%
Panther Drill 9 A1. Think about the law of conservation of matter. If a 13 gram
sample of element X combines with a 34.7 gram sample of element Y, to form compound XY, what will the mass of compound XY be?
2. A 25.3 sample of an unknown compound contains .0.8 grams of oxygen. What is the mass percent of the oxygen in the unknown compound?
3. When mercury oxide is heated it breaks down into its components of mercury and oxygen. 28.4 grams completely breaks down it yields 2.0 grams of oxygen. What is the mass percent of mercury in mercury oxide?
`
Panther Drill 10
In your own words, define the law of conservation of mass and the law of
definite proportion.
Prentice Hall © 2003 Chapter 1
Law of Multiple Proportion
States: when different compounds are formed by the combination of the elements X and Y, then the ratios between elements change, one element is usually consistent in its subscript while the other usually changes.
ie. H2O and H202
The H stays consistent and the Oxygen subscript changes
Law of Multiple ProportionEXAMPLE
Lets compare 2 different compounds a containing copper and chlorine.
Compound 1 contains 64.2% copper and 35.8 % Chlorine.
Compound 2 contains 47.27 % Copper and 52.73 % Chlorine.
Law of Multiple Proportion
Now we have to determine the RATIO of copper to Chlorine in each Compound. To do that we divide the Mass % of the copper by the mass % of the chlorine in each compound
Formula: Mass % element 1 Mass % Element 2
= Ratio of g Element 1 per g Element 2
Law of Multiple Proportion
Compound 1:
64.2 % Cu = 1.796 g Cu : 1 g Cl35.8 % Cl
Law of Multiple Proportion
Compound 2:
47.27% Cu = .8964 g Cu : 1 g Cl52.73 % Cl
Law of Multiple Proportion
Now we find the ratio of copper between compound 1 and compound 2
1.796 g Cu/1 g Cl = 2.008.964g Cu /1 g Cl
SOThe ratio is 2: 1
Compound 1 : Compound 2
Law of Multiple Proportion
This is important because there are only about 116 elements n the world and multiple proportion allows for exponentially more compounds
Try This 1Draw table and fill in the information
CompoundTotal Mass Compound
Mass Iron
Mass Oxygen
Mass % Iron
Mass % Oxygen
A 75.00 g 52.46 g 22.54 g
B 56.00 g 43.53 g 12.47 g
Mass % = Mass Element x 100 Mass Compound
CompoundTotal Mass Compound
Mass Iron
Mass Oxygen
Mass % Iron
Mass % Oxygen
A 75.00 g 52.46 g 22.54 g 70 % 30 %
B 56.00 g 43.53 g 12.47 g 77.7 % 22.3 %
Mass % Compound A= Fe: 52.46/75.00 x 100 = about 70 % O: 100 % - 70% = 30 %
Mass % Compound B= Fe: 43.53/56 x 100 = about 77.75 % O: 100 % - 76% = 22.25%
Use the Law of Multiple proportion to find the ratio between Compound A and
Compound B from the table.
Mass Ratio Formula For a Compound:Mass of Element 1 (Fe)Mass Element 2 (O) 52.46 g Fe 22.54 g O
Compound A Ratio= 2.33 g Fe/ 1 g O
You Do Compound B
43.53 g Fe 12.47 g O
= 3.5 g Fe/g O in Compound B
Now compare compound A to Compound B3.49 g Fe Comp B/ 2.33 g Fe Comp A =3.5 g Fe Comp B: 2.33 g Fe Comp. A
Chapter 4
Friday: 4.1TSWBAT:Define and atom Create a time line citing the key milestones
leading to the modern atomic theory.
Panther Drill # 11
Brainstorm Quick Write:Just “stream of consciousness” write and put
down as many facts that you can think of about the atom!!!
Early Theories of matter and atomsGreek Philosopher Democritus about 400 BC
• 1st to suggest atoms• 1st to suggest matter is empty space that atoms
move through• Atoms were solid and could not be divided into
any thing smaller.• Atoms were of different sizes and shapes• Properties depended on shape, size and
movement of atoms
Early Theories of matter
Greek Philosopher Aristotle about 350 BC• He was the “Rock Star” of his time• He rejected Democritus’s Ideas because the were
opposite of his.
Early Theories of matter
Not much new progress made for about 2100 years or so
Early Theories of matterJohn Dalton 1766-1844
• All elements are made up of atoms. It is impossible to divide or destroy an atom.
• All atoms of the same elements are alike.
• Atoms of different elements are different.
• Atoms of different elements combine to form a compound.
Early Theories of matter
J.J. Thompson Late 1800’s• English scientist. • He discovered the electron when he was
experimenting with gas discharge tubes.• He saw that they moved to the positive end of the
gas tube and figured out that they had a – charge.
Thompson’s PlumPudding Model
Early Theories of matter
Lord Ernest Rutherford 1871-1937 • Famous for gold foil experiment that showed that
some + charged particles could pass through a thin layer of gold foil and some bounced back proving that matter contained empty space and atoms had a + charged nucleus that made some particles “bounce back”.
Early Theories of matterNiels Bohr Early 1900’s
• He proposed a model of the atom that is similar to the model of the solar system.
• There are different energy levels or electron orbits around the nucleus, like the different planets orbit the sun at different distances.
Bohr Model Nitrogen
Your Assignment: Use the notes you have plus the book if you have it to create
a time line the tells the story of the development of the atomic theory.
Use color and try to make it as neat as you can the best will be put up on the wall of fame.
The Assignment is due Monday 10/18 and is worth 15 points it will be graded as follows:
6-7 Entries 12 points5 entries 11 points2-4 entries 8 points1 entry 5 pointsNeatness, and Creativity can get you up to 3 points
EXAMPLE OF A TIME LINE
http://www.bing.com/images/search?q=Example+of+timeline&FORM=SSIR&adlt=strict#focal=407f79a01ce488aee10015bab6c14733&furl=http%3A%2F%2Fwww.studentsfriend.com%2Fsfcimage%2Feras.jpg
Monday 10-18
1. PD 122. Demo Rutherford experiment3. Work on project
Panther Drill 12
In your opinion who do you think is the most important person in the development of the modern atomic theory. Use your notes and your own research to decide.
Panther Drill #13 Period 1Write down 2 possible test questions
about atomic theory, on the paper on your desk. One can be a basic question, one needs to be a harder extended response type question using question stems for analyzing and applying for the second question. PLEASE WRITE IN THE ½ SHEETS YOU HAVE AND NOT THE FULL SHEETS.
Panther Drill #13Particle Location Charge Size
Electron
Proton
Neutron
Create and fill in the blanks in the table, for size rank the particles 1 2 or 3 for size
AtomsThe Atom:
Smallest particle of matter that will retain its properties.
Size: A single copper atom is .000000000128 or 1.28 x 10 -10 meters in diameter.
The only way it is possible to see an atom is to use a scanning tunneling microscope STM, a very fine sharp point is moved over a sample and it interacts w/ the superficial or surface atoms and this interaction is recorded by a computer.
STM images
Silicon Nickel
STMsInformational Only
STMs are allowing science to start to develop “nanotechnology” meaning they are able to build machines the size of a molecule, 1 atom at a time.
Here is an example of a scientist w/ too much time on their hands!!!!!!
ElectronsFormally discovered to have a negative charge and a
definitive mass, by JJ Thompson in 1897, use a cathode ray tube.
The strength of the – charge was determined by Millikan and the oil drop experiment.
The electron was found to have a mass of 1/1840 of 1 Hydrogen atom or 9.1 x 10 -28 grams.
Electron Cloud
Electrons are not really in defined orbitals, but are found in a cloud.
The cloud shows where the electrons are likely to be at any given time.
Heisenberg uncertainty principle
A math equation that states position and momentum, cannot be simultaneously known to high precision.
Means that we can either know what way an electron is moving or where it is but not both at the same time.
Schrödinger's catSchrödinger's cat is a thought experiment, often
described as a paradox, devised by Austrian physicist Erwin Schrödinger in 1935. It illustrates what he saw as the problem of the Copenhagen interpretation of quantum mechanics applied to everyday objects. The thought experiment presents a cat that might be alive or dead, depending on an earlier random event. In the course of developing this experiment, he coined the term quantum entanglement.
Quarks
There are six quarks, these are the particles that make up protons and neutrons for our purposes we will deal with up and down quarks.
Up quarks have a + 2/3 chargeDown quarks have a -1/3 charge
Protons, Neutron and the Nucleus
Protons:Found by Rutherford Charge of +1Mass 1.673 x 10 -28
Protons, Neutron and the Nucleus
Neutron: Confirmed by James Chadwick in 1932Charge : Neutral or 0Mass 1.673 x 10 -28
To Sum it Up
a.m.u. = atomic mass unit, about 1 proton or neutron of a Hydrogen atom.
Panther Drill # 14
1. Sketch an atom.2. How many Protons, Neutrons and
Electrons are in the following element.
Different ElementsWe know protons and neutrons are in the nucleus
and electrons are outside but how do atoms for different elements vary? I mean how is Hydrogen different from Helium?
See the atomic # on the periodic table H=1 and He = 2 ect
This means that H has 1 proton and 1 electronAnd Helium has 2 protons and 2 electrons
***REMEMBER # OF ELECTRONS = # PROTONS IN A NORMAL ATOM***
Reading the Periodic Table
Atomic Number
Elements Symbol
Chemical NameAverage Atomic
Mass
Reading the Periodic TableNo need to write this
Remember not all periodic tables are as detailed as others some have more information than the basics like this one.
NeutronsLets look at Hydrogen and Helium on the
periodic table
We see the atomic #, but what is the number underneath the symbol?
THAT IS THE ATOMIC MASS
To find the # of Neutrons all we do is round the atomic mass to the nearest whole number. This is called the mass number Try it w/ H and HeH= 1 He = 4
Then we subtract the # of protons from the MASS NUMBER NEUTRONS = MASS NUMBER - #PROTONS
H: 1-1 =0 (no neutrons in Hydrogen)He 4 – 2 = 2 (2 neutrons in Helium)
Lets Try Some Get w/ a PartnerHow Many protons neutrons and electrons in
Lithium?
In Carbon?
In Zinc (Zn)?
MASS NUMBER = 6.941 = 7 Atomic # = 3 Protons = atomic # = 3 Electrons = protons = 3
Neutrons = MASS NUMBER - # protons = 7 - 3 4 Neutrons
MASS NUMBER = 12.011 = 12 Atomic # = 6 Protons = atomic # = 6 Electrons = protons = 6Neutrons = MASS NUMBER - # protons = 12 - 6 6 Neutrons
MASS NUMBER = 65.39 = 65 Atomic # = 30 Protons = atomic # = 30 Electrons = protons = 30Neutrons = MASS NUMBER - # protons = 65 -30 35 Neutrons
Run it backWhat element has 5 neutrons and 4 protons.
Atomic # = # Protons = 4 = Beryllium
What is the name of the element with 31 neutrons and 28 ELECTRONS? What is the element?
# of electrons = # protons = atomic # = 28 =Nickel = 58.69 (atm mass)
Try Some on Your Element Sheet
Panther Drill 15
1. How many protons, neutrons and electron does Gold have?
2. What is a isotope?3. How do you explain hydrogen with 2
protons?
Isotope Video Clip
Isotopes LCHS Laptop
Isotopes Flash Drive
Isotopes
Hydrogen has 3 different isotopes.
Atoms that have the same number of protons but different numbers of neutrons. Most atoms have isotopes.
http://education.jlab.org/glossary/isotope.html
Isotopes
Remember# Neutrons = Mass # - Atomic #
SOMass # = atomic # (aka # protons) +
# neutrons.
http://education.jlab.org/glossary/isotope.html
Isotope
Carbon has 2 isotopes
Carbon-12&
Carbon-14
Isotopes
Find out the number of neutrons in an isotope the same way as in a normal element.
NEUTRONS = MASS NUMBER - ATOMIC # OR PROTONS
Isotope NotationHow do I write and isotope?
SymATM #
Mass #
How would you write the isotopes of copper:a) 1 w/ a mass number of 63b) 1 w/ a mass # of 65
a)
Cu
b) Cu
How would you write the isotopes of copper:a) 1 w/ a mass number of 63b) 1 w/ a mass # of 65
63 Mass #
29 # protons
65 Mass #
29 # protons
Why not whole # atomic mass
Elements have isotopes so we don’t whole # atomic masses.
Atomic mass = Atomic #
Elements and their isotopes occur in different natural abundances
To find the atomic mass we use a weighted average
Weighted Average
If a 75% of the apples in a box have a mass of 149 grams and 25 % of the apples a mass of 153 grams. What is the average mass of an apple in the box?
Formula: [mass (item1) + (% item1 x .01)] X [mass (item2)x (% item2
x .01)]
Weighted Average[mass (item1)x (% item1 x .01)] + [mass (item2)x (% item2 x .01)]
Item 1 = Apple 1 = mass 149g and 75% abundanceItem 2 = Apple 2 = mass 153g and 25% abundance
Avg. mass of apple =[149 g x (75% x .01)] + [ 153 g x (25% x .01)
111.75g + 38.25g = 150 g
The average apple has a mass of 150 grams
Class Work
Do Problems 18 and 24 on page 121 in your book
on handout
Let me see at least 18 before you leave!!!
Panther Drill 16
1. Silver has 2 isotopes 107 & 109 47 47
Ag Ag
Based on Silvers atomic mass from the periodic table, which isotope is more abundant??
Agenda 10/25
1. Panther Drill 17 (3 Q’s 1 review from last week and 2 to assess pre-knowledge of today’s topic)
2. Notes and Discussion (Teacher will explain Nuclear rxns, Radioactive decay (Unstable Nuclei), alpha, beta, and gamma radiation).
3. WS 4.4 From Text.4. Thumbs up or Down Review.
Panther Drill 171. Why do elements have on the periodic table
have decimals in their atomic masses instead of whole numbers.
2. What is radiation?3. What is a nuclear reaction?
Radioactivity• Discovered in 1890s when scientists noticed
energy constantly being emitted they called this radioactivity.
• This energy was called radiation.• Atoms that emit radiation are called radioactive
atoms.• The energy emitted was in the form of particles
and rays of energy.
Nuclear reactions• It was found the radioactive atoms were not
undergoing a chemical reaction but what is called a nuclear reaction.
• Nuclear reactions are changes in the nucleus of an atom where energy is released.
• Atomic nuclei that emit energy through nuclear reactions are called unstable.
• After the unstable nuclei release energy and become stable, they become new isotopes or even other elements. This is called radioactive decay.
Radioactive decay
In an experiment shows the 3 types of radiation
Negative charged plate
Positive charged plate
Alpha Radiation
Alpha particles are the form of radiation that is drawn to the neagative charged plate in the experiment.
An alpha particle contains 2 protons and 2 neutrons so it is the same as a helium atom.
Alpha particle is shown as 4HE or a2
Beta RadiationBeta particles were drawn to the + charged plat in the
experiment. A beta particle is really and – charged electron and is
shown as an electron or b particle
This release allows the neutron to change to proton
b
Gamma Radiation• Gamma radiation or g
is the only of the 3 types to be an energy ray instead of a particle
• It is not influenced by the + or – charged plate.
• It has no mass whereas the other 2 do.
Agenda 10/271. PD # 18 (3 Q’s, 1 review and 2 to assess prior
knowledge.) (7 min)2. Notes/Discussion (Students will be re-introduced to
electron configuration models, Including Bohr Models) (15 min)
3. Guided Practice (Instructor will model for students creating Bohr models) (5-10 min)
4. Students will illustrate electron configurations using Bohr models, of simple atoms in pairs. Instructor will observe and assist struggling students. (15 min)
5. Some groups will show their models on the Prom Board.
Panther Drill 181. What are the differnece between alpha and beta
radiation.2. How many electrons are in a Carbon atom?3. How do you show them in a Bohr Model?
Electron distributionWe will talk a lot more about electrons in a month or
so but lets look at how to create models of the atoms showing electrons, protons, and neutrons.
Now in reality we know that the electrons exist in electron clouds around the nucleus, but we will use MODELS that show them in orbitals like the a solar system. These are called BOHR MODELS.
Electron Cloud vs Bohr ModelCHLORINE
Electron Cloud Bohr Model
Electron Orbitals
Orbitals are abbreviated as n.
There are more than can be as many as 7 orbitals or energy levels.
Nucleus
n=1
n=3n=2
n=4n=5
Electron OrbitalsMax
Electrons for each n level.
Level1 2 e-Level2: 8e-Level3 18e-Level 4 32e-Level 5 50e-
Nucleus
N=1
N=3N=2
N=4N=5
50 e-32 e-
18 e-
8 e-
2 e-
Lets try someAtom with 3 protons
and 3 neutronsAtom with 7 protons
and 6 neutrons.
Panther Drill # 191. What is the difference between the Bohr
model and the “more realistic” electron cloud model?
2. What are valance electrons?3. Is this Bohr model correct, if not why?
e-e-
e-
e-
e-e- 5P4N
Valence Electrons• The electrons in the outermost shell are the
valence electrons • The valance electrons are the electrons on an
atom that can be gained or lost in a chemical reaction.
e-
e-
e-
e-
e-e-
What element is this?
How do you know?
Where are the valence electrons?
13 P14N
e- e-e-
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Volunteer or Victim Circle the valence electrons
Review of BohrMax
Electrons for each n level.
Level1 2 e-Level2: 8e-Level3 18e-Level 4 32e-Level 5 50e-
Nucleus
n=1
n=3n=2
n=4n=5
50 e-32 e-
18 e-
8 e-
2 e-
ProjectYou will be assigned your choice of a poster project of
an atom or creating a 3-D Bohr model of an atom. It is your choice the assignments can be seen in full on the assignment sheet handout. When you have decided then get a full handout that includes the rubric, real quick let’s look at some examples of real creative 3-D models from other students.
3D EXAMPLES
The basics of the projects can also be seen on the front bulletin board if you can need them.
3-D Model Due Friday 11/5• Your 3 D model of your atom is DUE ‐ ON Friday 11/5. • In addition to your 3-D model, you should include a short write up
that includes al of the following list:• Element Name • Atomic number • Chemical symbol • Metal/non metal/metalloid? ‐• State or phase at room temp. • Uses • Any interesting facts • Characteristics or properties • Number of electrons, neutrons, and protons
• The elements you have to choose from for the 3-D model are Hydrogen through Argon on the periodic table. If you need to see examples again go to website (Power Point Note section) and look at the 3-D model Power Point.
Poster Due Wednesday 11/3• Along with a Bohr model drawing of your atom your poster must
display the following information on the front so it can be seen:• Element Name • Atomic number • Chemical symbol • Metal/non metal/metalloid? ‐• State or phase at room temp. • Uses • Any interesting facts • Characteristics or properties • Number of electrons, neutrons, and protons
• Your choices for your Bohr Model atom posters are any atom from sodium and higher in atomic number on the periodic table.
Exit Ticket Name________________________________
13 P14N
e- e-e-
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1. Circle the valence electrons. What is their function.
2. On the back sketch and label a Bohr model of Silicon or Magnesium
Drop in basket before you leave.
HAVE A GREAT DAY!!
13 P14N
e- e-e-
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e-e-
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1. Circle the valence electrons. What is their function.
2. On the back sketch and label a Bohr model of Silicon or Magnesium
Drop in basket before you leave.
HAVE A GREAT DAY!!
Exit Ticket Name________________________________
Panther Drill 20
Define valence electrons and state their main job in the atom.
Heisenberg Uncertainty Principle(review)
• The Heisenberg Uncertainty Principle says - loosely - that you can't know with certainty both where an electron is and where it's going next.
• What it actually says is that it is impossible to define with absolute precision, at the same time, both the position and the momentum of an electron.
PurposeElectron configuration notation is a written and
visual and written method of noting every thing we can about 1 given electron in an atom’s ground state.
Ground state: the atom’s lowest most stable energy state or condition. This the condition represented on the periodic table.
Orbitals and principal quantum numbersAs we learned with Bohr models, n = the electron
energy levels or orbitals.n is also referred to as the principal quantum level.
Trends• As n increases, the orbital becomes larger and the
electron becomes farther from the nucleus.
• As n increases the amount of energy of the electrons increase.
ADD THIS: The higher the quantum levels are less stable than the lower levels.
In the Bohr Model
Nucleus
Princip
al Quantum Le
vel 1
Princip
al Quantum Le
vel 2
Principal Quantum Level 3
Sublevels Principal energy levels contain energy
sublevels or orbitals.(n=1) Principal energy level 1 contains 1
sublevel(n=2) Principal energy level 2 contains 2
sublevels(n=3) Principal energy level 3 contains 3
sublevels
Sub-levels Sublevels are labeled s, p, d, or f
depending on their shape
S orbitals
s orbitals are spherically and symmetric around the nucleus
P orbitals
A p orbital is rather like 2 identical balloons tied together at the nucleus.
P orbitalsAt any energy level (or
n level) it is possible to have 3 p orbitals or sub-levels at right angles to each other
P sub shell can have a total of 6 e- (2 in each orbital)
D sub level
“d” sub level has 5 orbital and can hold 10 electrons.
“d” does not start to get filled untill after 4s is filled.
F sub level“f” orbital has 7 orbitals, and the first ‘”f”
orbital is seen in the 4th energy level.4f does not begin to fill until after level 6s is
full.
Aufbau PrincipleThe Aufbau principle states that
each electron occupies the lowest energy level available.
This is the order they fill up in.
Just follow the arrow.
Start here and follow the arrow
Hund's Rule
Within a subshell, the electrons will occupy the orbitals by themselves first, and will only pair up when there are no longer any empty orbitals available in that subshell.
Would you want to share a room with
someone if you didn’t have to?
The Pauli Exclusion Principle This principle says that an orbital is filled when
it contains 2 electrons. After that, you have to put the electrons in a different orbital.
Each type of subshell (sublevel) contains a different number of orbitals. And, each orbital can hold ONLY 2 electrons.
The Pauli Exclusion Principle
Subshell Type # of Orbitals Maximum # of Electrons
s 1 2
p 3 6
d 5 10
f 7 14
Write the notation this way1s
4s
3d
3 p
3s
2s
2 pThe arrows point in opposite directions in each box because they spin in opposite directions because the – charges repel each other
Carbon= 6 electrons It fills like this
Write the notation this way1s
4s
3d
3 p
3s
2s
2 p
The arrows point in opposite directions in each box because they spin in opposite directions because the – charges repel each other
Why do the fill each box w/ one arrow 1st
Lets try some
1s
4s
3d
3 p
3s
2s
2 p
Panther Drill 21 1.How many electrons can be in each
ORBITAL ?2.Complete the electron configuration for
Fluorine.
1s
2s
2 p
Panther Drill #221. In what order do the following sublevels fill
up with electrons? 4s 3s 2p 3d 2s 3p 1s2. How many valence electrons are in N and in
Mg?
Written Electron ConfigurationAfter the standard orbital notation (boxes and arrows), we need to know how use written electron notation.
This is much simpler!
All you do is look at the boxes and write out what is in them.
Written Electron Configuration
1s 2s 2 p
Write this as follows:
1s22s22p3
2p3
n or quantum level
Sub Level
Number of electrons in the sub level.
Write the correct
electron notation
and identify the
element.
1s
2s
2p
3s3p
4s3d
4p
1s2 2s2 2p6 3s2 3p4
Atomic # 16SSulfur
Write the correct
electron notation
and identify the
element.
1s
2s
2p
3s3p
4s3d
4p
1s2 2s2 2p6 3s2 3p6 4s2 3d10 4p4
Atomic # 34SeSelenium
Panther Drill 23
In electron notation (not box and arrow diagrams), write the notation for the following elements:
a) Oxygenb) Neonc) Argon 1s22s22p63s23p6 4s23d104p6
1s22s22p4
1s22s22p6
Still a lot of writing?We can use the Noble Gas Notation. Noble
gases come from group 18 on the periodic table
Put the noble gas symbol in brackets [Ne] to show that the all levels in it are full and stable.
Then use notation to show the electrons in the outermost orbital.
Try Magnesium in your notes Mg = [Ne] 3s2
In your notes
Write the noble gas notation for:Nitrogen
Calcium
Copper
Orbital Filling Periodic Table
3p
2s
3s
7s
6s
5s
4s
1s
4d
4p
5p
6p
2p
3d
5d
6d
4f
7p when more discovered
5f
Orbital Filling Periodic Table Fill-in
GO TO ACTIVE INSPIRE ELECTRON DOT
DIAGRAM
Electron Dot DiagramsBecause valence electrons are the ones that are
involved in CHEMICAL BONDING, we often represent them in a visual short-hand called electron dot diagrams or Lewis diagrams.
These are simple to do, they only show the valence electrons. So for the simplest atoms like we will look at
Lewis or electron Dot Diagrams
Here is an example:
Phosphorus has how many valence electrons? 5
Fill in the Electrons in this order.
He4th e-
2nd e-
3rd e- 1st e-
7th 5th
6th
8th
Panther Drill Take a few minutes to either study or add
to your cheat sheets. If you can do this reasonably quietly, you can have up to 10 min. As soon as it becomes too loud, you will not have any more time and we will start the test.
Notebooks for unit 2 will be checked after you turn your test in.