Kentucky Core Content

SC-08-1.1.1 Students will: interpret models/representations of

elements; classify elements based upon patterns in

their physical (e.g., density, boiling point, solubility) and chemical (e.g., flammability, reactivity) properties.

Core Content Cont.

SC-08-1.1.2 Students will understand that matter is made of

minute particles called atoms, and atoms are composed of even smaller components. The components of an atom have measurable properties such as mass and electrical charge. Each atom has a positively charged nucleus surrounded by negatively charged electrons. The electric force between the nucleus and the electrons holds the atom together.

Core Content Cont.

SC-08-1.1.3Students will understand that the atom’s

nucleus is composed of protons and neutrons that are much more massive than electrons.

Investigating Atoms and Atomic Investigating Atoms and Atomic TheoryTheory

Students should be able to:Students should be able to:Describe the particle theory of matter. Describe the particle theory of matter. Use the Bohr model to differentiate among the Use the Bohr model to differentiate among the

three basic particles in the atom (proton, three basic particles in the atom (proton, neutron, and electron) and their charges, neutron, and electron) and their charges, relative masses, and locations. relative masses, and locations.

Compare the Bohr atomic model to the electron Compare the Bohr atomic model to the electron cloud model with respect to their ability to cloud model with respect to their ability to represent accurately the structure of the atom.represent accurately the structure of the atom.

Why do physicists study particles? Physicists study particles because everything is made of them, including us! People have been trying to understand what the Universe is made of forever. One of the earliest theories said that everything could be built from just four elements, Earth, Air, Fire and Water. This was a great scientific theory because it was simple. But it had one big drawback: it was wrong. WHY?

Atomos: Not to Be CutAtomos: Not to Be Cut

The History of Atomic TheoryThe History of Atomic Theory

Atomic ModelsAtomic Models This model of the This model of the

atom may look atom may look familiar to you. This is familiar to you. This is the Bohr model. In the Bohr model. In this model, the this model, the nucleus is orbited by nucleus is orbited by electrons, which are electrons, which are in different energy in different energy levels. levels. A model uses familiar ideas to A model uses familiar ideas to

explain unfamiliar facts explain unfamiliar facts observed in nature.observed in nature.

A model can be changed as A model can be changed as new information is collected.new information is collected.

The atomic model The atomic model has changed has changed throughout the throughout the centuries, starting centuries, starting in 400 BC, when it in 400 BC, when it looked like looked like a a billiard ball billiard ball →→

Who are these men?Who are these men?

In this lesson, we’ll learn about the men whose quests for knowledge about the fundamental nature of the universe helped define our views.

DemocritusDemocritus

This is the Greek This is the Greek philosopher Democritus philosopher Democritus who began the search for who began the search for a description of matter a description of matter more than more than 24002400 years ago. years ago. He asked: Could matter He asked: Could matter

be divided into smaller be divided into smaller and smaller pieces and smaller pieces forever, or was there a forever, or was there a limitlimit to the number of to the number of times a piece of matter times a piece of matter could be could be divideddivided? ?

400 BC

AtomosAtomos

His theory: Matter could not His theory: Matter could not be divided into smaller and be divided into smaller and smaller pieces forever, smaller pieces forever, eventually the smallest eventually the smallest possible piece would be possible piece would be obtained.obtained.

This piece would be This piece would be indivisible.indivisible.

He named the smallest He named the smallest piece of matter “atomos,” piece of matter “atomos,” meaning “not to be cut.”meaning “not to be cut.”

AtomosAtomos

To Democritus, atoms To Democritus, atoms were were smallsmall, hard , hard particles that were all particles that were all made of the same made of the same material but were material but were differentdifferent shapes and shapes and sizes.sizes.

Atoms were Atoms were infiniteinfinite in in number, always number, always moving and capable of moving and capable of joining together.joining together.

This theory was This theory was ignored and forgotten ignored and forgotten for more than for more than 2000 2000 years!years!

The eminent The eminent philosophers of philosophers of the time, the time, AristotleAristotle and and Plato, had a Plato, had a more more respected, respected, (and ultimately (and ultimately wrongwrong) theory.) theory.

Aristotle and Plato favored the earth, fire, air and water approach to the nature of matter. Their ideas held sway because of their eminence as philosophers. The atomos idea was buried for approximately 2000 years.

Dalton’s ModelDalton’s Model

In the early 1800s, In the early 1800s, the English the English Chemist John Chemist John Dalton Dalton performed a performed a number of number of experiments that experiments that eventually led to eventually led to the acceptance of the acceptance of the idea of atoms.the idea of atoms.

Dalton’s TheoryDalton’s Theory

He deduced that all He deduced that all elementselements are composed of are composed of atoms. Atoms are atoms. Atoms are indivisible and indivisible and indestructible particles.indestructible particles.

Atoms of the Atoms of the samesame element element are exactly alike.are exactly alike.

Atoms of Atoms of differentdifferent elements elements are are differentdifferent..

CompoundsCompounds are formed by are formed by the joining of atoms of two the joining of atoms of two or more elements.or more elements.

..

This theory This theory became one became one of the of the foundations foundations of modern of modern chemistry.chemistry.

Thomson’s Plum Pudding Thomson’s Plum Pudding ModelModel

In In 18971897, the , the English scientist English scientist J.J. Thomson J.J. Thomson provided the first provided the first hint that an atom hint that an atom is made of even is made of even smallersmaller particles. particles.

Thomson ModelThomson Model He proposed a He proposed a

model of the atom model of the atom that is sometimes that is sometimes called the “called the “PlumPlum PuddingPudding” model. ” model.

Atoms were made Atoms were made from a positively from a positively chargedcharged substancesubstance with negatively with negatively charged electrons charged electrons scatteredscattered about, like about, like raisins in a pudding.raisins in a pudding.

Thomson ModelThomson ModelThomson Thomson

studied the studied the passage passage of an of an electric current electric current through a gas.through a gas.

As the current As the current passed through passed through the gas, it gave the gas, it gave off rays of off rays of negatively negatively charged charged particles.particles.

Thomson ModelThomson Model

This surprised This surprised Thomson, Thomson, because the because the atoms of the gas atoms of the gas were uncharged. were uncharged. Where had the Where had the negative charges negative charges come from?come from?

Where did they come from?

Thomson concluded that the negative charges came from within the atom.

A particle smaller than an atom had to exist.

The atom was divisible!

Thomson called the negatively charged “corpuscles,” today known as electrons.

Since the gas was known to be neutral, having no charge, he reasoned that there must be positively charged particles in the atom.

But he could never find them.

Rutherford’s Gold Foil Rutherford’s Gold Foil ExperimentExperiment

In 1908, the English In 1908, the English physicist Ernest physicist Ernest Rutherford was hard Rutherford was hard at work on an at work on an experiment that experiment that seemed to have little seemed to have little to do with unraveling to do with unraveling the mysteries of the the mysteries of the atomic structure.atomic structure.

Rutherford’s experiment Involved firing Rutherford’s experiment Involved firing a stream of tiny a stream of tiny positively chargedpositively charged particles at a thin sheet of particles at a thin sheet of gold foilgold foil (2000 atoms thick)(2000 atoms thick)

MostMost of the positively of the positively charged “bullets” passed charged “bullets” passed right through the gold right through the gold atoms in the sheet of atoms in the sheet of gold foilgold foil without changing without changing course at all.course at all.

SomeSome of the positively of the positively charged “bullets,” charged “bullets,” however, did bounce however, did bounce away from the gold sheet away from the gold sheet as if they had hit as if they had hit something something solidsolid. He . He knew that positive knew that positive charges charges repelrepel positive positive charges.charges.

http://chemmovies.unl.edu/ChemAnime/RUTHERFD/RUTHERFD.html

http://chemmovies.unl.edu/ChemAnime/RUTHERFD/RUTHERFD.html

This could only mean that the gold atoms in the This could only mean that the gold atoms in the sheet were mostly sheet were mostly open spaceopen space. Atoms were . Atoms were notnot a pudding filled with a positively charged a pudding filled with a positively charged material.material.

Rutherford concluded that an atom had a Rutherford concluded that an atom had a small, small, dense, positively charged centerdense, positively charged center that that repelledrepelled his positively charged “bullets.”his positively charged “bullets.”

He called the center of the atom the “He called the center of the atom the “nucleusnucleus”” The nucleus is The nucleus is tiny tiny compared to the atom as a compared to the atom as a

whole. whole.

RutherfordRutherford

Rutherford reasoned Rutherford reasoned that all of an atom’s that all of an atom’s positively charged positively charged particles were particles were containedcontained in the in the nucleus. The nucleus. The negatively charged negatively charged particles were particles were scatteredscattered outside the outside the nucleus around the nucleus around the atom’s atom’s edgeedge..

Bohr ModelBohr ModelIn 1913, the Danish In 1913, the Danish

scientist Niels Bohr scientist Niels Bohr proposed an proposed an improvement. In his improvement. In his model, he placed model, he placed each electron in a each electron in a specificspecific energy energy level.level.

Bohr ModelBohr Model According to Bohr’s According to Bohr’s

atomic model, atomic model, electrons move in electrons move in definite definite orbitsorbits around around the nucleus, much the nucleus, much like planets circle the like planets circle the sun. These orbits, or sun. These orbits, or energy energy levelslevels, are , are located at certainlocated at certain distances from the distances from the nucleus.nucleus.

Wave Model

The Wave ModelThe Wave ModelToday’s atomic Today’s atomic

model is based on model is based on the principles of the principles of wavewave mechanicsmechanics..

According to the According to the theory of wave theory of wave mechanics, mechanics, electrons electrons do not do not movemove about an about an atom in a atom in a definite definite path,path, like the like the planets around the planets around the sun.sun.

The Wave ModelThe Wave Model

In fact, it is In fact, it is impossibleimpossible to determine the exact to determine the exact location of an electron. The location of an electron. The probableprobable location of location of an electron is based on how much an electron is based on how much energyenergy the the electron has.electron has.

According to the modern atomic model, an atom According to the modern atomic model, an atom has a has a small positively charged nucleussmall positively charged nucleus surrounded by a large region in which there are surrounded by a large region in which there are enough electrons to make an atom neutral.enough electrons to make an atom neutral.

Electron Cloud:Electron Cloud: A space in which A space in which

electrons are likely to be electrons are likely to be found.found.

Electrons Electrons whirlwhirl about the about the nucleus billions of times nucleus billions of times in one secondin one second

They are not moving They are not moving around in around in randomrandom patterns.patterns.

Location of electrons Location of electrons depends upon how much depends upon how much energyenergy the electron has. the electron has.

Electron Cloud:Electron Cloud:

Depending on their energy they are locked into a Depending on their energy they are locked into a certain area in the cloud.certain area in the cloud.

Electrons with the Electrons with the lowestlowest energy are found in energy are found in the energy level the energy level closestclosest to the nucleus to the nucleus

Electrons with the Electrons with the highesthighest energy are found energy are found in the in the outermostoutermost energy levels, farther from energy levels, farther from the nucleus.the nucleus.

IndivisibleIndivisible ElectronElectron NucleusNucleus OrbitOrbit Electron Electron CloudCloud

GreekGreek XX

DaltonDalton XX

ThomsonThomson XX

RutherfordRutherford XX XX

BohrBohr XX XX XX

WaveWave XX XX XX

List 3 key points from today’s lesson on atomic theory history.

Journal Journal Compare and contrast physical and Compare and contrast physical and

chemical changes in matter.chemical changes in matter.

You may use any graphic organizer you You may use any graphic organizer you wish to complete this journal.wish to complete this journal.

Atomic Structure

Core Content for AssessmentCore Content for Assessment

SC-08-1.1.3SC-08-1.1.3 Students will understand that the atom’s nucleus is Students will understand that the atom’s nucleus is

composed of protons and neutrons that are much more composed of protons and neutrons that are much more massive than electrons.massive than electrons.

SC-08-1.1.2SC-08-1.1.2 Students will understand that matter is made of minute Students will understand that matter is made of minute

particles called atoms, and atoms are composed of even particles called atoms, and atoms are composed of even smaller components. The components of an atom have smaller components. The components of an atom have measurable properties such as mass and electrical charge. measurable properties such as mass and electrical charge. Each atom has a positively charged nucleus surrounded by Each atom has a positively charged nucleus surrounded by negatively charged electrons. The electric force between the negatively charged electrons. The electric force between the nucleus and the electrons holds the atom together.nucleus and the electrons holds the atom together.

Structure of an atom(page 256 in Sciencesaurus)

NucleusNucleus – The core of an atom. Contains – The core of an atom. Contains protons and neutrons.protons and neutrons.

ProtonsProtons – Positively (+) charged particles – Positively (+) charged particles found in the nucleus of an atom.found in the nucleus of an atom.

NeutronsNeutrons – Neutrally charged particles found – Neutrally charged particles found in the nucleus of an atom.in the nucleus of an atom.

ElectronsElectrons – Negatively (-) charged particles – Negatively (-) charged particles found outside the nucleus of an atom.found outside the nucleus of an atom.

Structure of an atom Valence electron – the fartheset away or most Valence electron – the fartheset away or most

loosely held electrons which help determine loosely held electrons which help determine how elements bond.how elements bond.

Electron Dot Diagram – A diagram in which Electron Dot Diagram – A diagram in which each dot represents one electron in the outer each dot represents one electron in the outer valence “shell”. (pg 268 in Sciencesaurus)valence “shell”. (pg 268 in Sciencesaurus)

Isotopes – Atoms of the same element that Isotopes – Atoms of the same element that have different number of neutrons (eg. have different number of neutrons (eg. Carbon)Carbon)

1st Verse:They’re tiny and they’re teeny,Much smaller than a beany,They never can be seeny,The Atoms Family.Chorus

2nd Verse:Together they make gases,And liquids like molasses,And all the solid masses,The Atoms FamilyChorus

3rd Verse:Neutrons can be found,Where protons hang around;Electrons they surroundThe Atoms Family.Chorus

Chorus:They are so small.(Snap, snap)They’re round like a ball.(Snap, snap)They make up the air.They’re everywhere.Can’t see them at all.(Snap, snap)

They’re tiny and they’re teeny,

Much smaller than a beany,

They never can be seeny,The Atoms Family.

They are so small.(Snap, snap)

They’re round like a ball.(Snap, snap)

They make up the air.They’re everywhere.Can’t see them at all.

(Snap, snap)

Together they make gases,And liquids like molasses,And all the solid masses,

The Atoms Family

They are so small.(Snap, snap)

They’re round like a ball.(Snap, snap)

They make up the air.They’re everywhere.Can’t see them at all.

(Snap, snap)

Neutrons can be found,Where protons hang around;

Electrons they surroundThe Atoms Family.

Journal

What is the name of this atom model and who was the scientist that created it?

Reviewing MatterReviewing MatterThree principal states of matterThree principal states of matter

SolidSolidLiquidLiquidGasGas

States of matterStates of matterSolid: molecules are tightly packed together; Solid: molecules are tightly packed together;

definite shape and volumedefinite shape and volumeLiquid: molecules are able to move around, but Liquid: molecules are able to move around, but

are still bonded; no definite shape, but definite are still bonded; no definite shape, but definite volumevolumeViscosity: the resistance of a liquid to flowing.Viscosity: the resistance of a liquid to flowing.

High viscosity flows slowlyHigh viscosity flows slowlyLow viscosity flows quicklyLow viscosity flows quickly

Gas: molecules are spread apart, filling the Gas: molecules are spread apart, filling the space available; no definite shape or volumespace available; no definite shape or volume

Characteristics of matterCharacteristics of matterBoiling point Boiling point (vaporization): the temperature at (vaporization): the temperature at

which a liquid changes to a gaswhich a liquid changes to a gasMelting pointMelting point: the temperature at which a solid : the temperature at which a solid

changes to a liquidchanges to a liquidCondensation pointCondensation point: the temperature at which a : the temperature at which a

gas turns to a liquid (the same temperature as gas turns to a liquid (the same temperature as the boiling point)the boiling point)

Freezing pointFreezing point: the temperature at which a : the temperature at which a liquid changes to a solid (the same temperature liquid changes to a solid (the same temperature as the melting point)as the melting point)

Changes in MatterChanges in Matter

Physical changePhysical change: alters the form of a : alters the form of a substance, but not its identitysubstance, but not its identityExamples: mixing salt and water, freezing Examples: mixing salt and water, freezing

waterwaterChemical changeChemical change: substances combine : substances combine

or break apart to form new substancesor break apart to form new substancesExamples: burning wood, heating sugar to Examples: burning wood, heating sugar to

make caramelmake caramel

Types of MatterTypes of MatterMixturesMixtures: two or more substances that : two or more substances that

are in the same place but are not are in the same place but are not chemically combinedchemically combinedExamples: Kool-aid, sea waterExamples: Kool-aid, sea water

Pure substancesPure substances: made of only one kind : made of only one kind of matter and has definite properties.of matter and has definite properties.

Pure SubstancesPure Substances

ElementsElements: a substance that cannot be : a substance that cannot be broken down into other substances by broken down into other substances by chemical or physical meanschemical or physical meansExamples: iron, copper, aluminumExamples: iron, copper, aluminum

CompoundsCompounds: a substance made of two or : a substance made of two or more elements that are chemically more elements that are chemically combinedcombinedExamples: sugar, saltExamples: sugar, salt

Clean sheet of paperClean sheet of paperPut your name on the paperPut your name on the paperNumber your page 1-22Number your page 1-22On the next slide, you will see a On the next slide, you will see a

list of items, place a “P” next to list of items, place a “P” next to the number if the change is the number if the change is physicalphysical

Place a “C” next to the number if Place a “C” next to the number if the change is chemicalthe change is chemical

1.1. Glass breakingGlass breaking2.2. Hammering wood together to build a Hammering wood together to build a

playhouseplayhouse3.3. A rusting bicycleA rusting bicycle4.4. Melting butter for popcornMelting butter for popcorn5.5. Glassblower creating sculptures out of glassGlassblower creating sculptures out of glass6.6. Freezing chocolate-covered bananasFreezing chocolate-covered bananas7.7. Separating sand from gravelSeparating sand from gravel8.8. Spoiling foodSpoiling food9.9. Burning toastBurning toast10.10. Making salt water to gargle for a sore throatMaking salt water to gargle for a sore throat11.11. Mixing lemonade powder into waterMixing lemonade powder into water

12.12.Cream being whippedCream being whipped13.13.Water evaporating from a pondWater evaporating from a pond14.14.Cutting grassCutting grass15.15.Burning leavesBurning leaves16.16.Humidifier putting moisture into the airHumidifier putting moisture into the air17.17.Corroding metalCorroding metal18.18.Bleaching your hairBleaching your hair19.19.Fireworks explodingFireworks exploding20.20.Squeezing oranges to get orange juiceSqueezing oranges to get orange juice21.21.Frying an eggFrying an egg22.22.Pouring milk on your oatmealPouring milk on your oatmeal

JournalPage 79 in book

1.Write a conclusion for your lab yesterday about whether or not your substances were changed physically or chemically.

2.Describe the arrangement of the periodic table.

3.Explain what kind of information can be found on the periodic table?

Elements and the Periodic Elements and the Periodic TableTable

(page 265 in Sciencesaurus)(page 265 in Sciencesaurus)

Core Content for Core Content for AssessmentAssessmentSC-08-1.1.1SC-08-1.1.1

Students will:Students will: interpret models/representations of elements;interpret models/representations of elements; classify elements based upon patterns in their physical (e.g., classify elements based upon patterns in their physical (e.g.,

density, boiling point, solubility) and chemical (e.g., density, boiling point, solubility) and chemical (e.g., flammability, reactivity) properties. flammability, reactivity) properties. 

Models enhance understanding that an element is composed of Models enhance understanding that an element is composed of a single type of atom. Organization/interpretation of data a single type of atom. Organization/interpretation of data illustrates that when elements are listed according to the illustrates that when elements are listed according to the number of protons, repeating patterns of physical (e.g., density, number of protons, repeating patterns of physical (e.g., density, boiling point, solubility) and chemical properties (e.g., boiling point, solubility) and chemical properties (e.g., flammability, reactivity), can be used to identify families of flammability, reactivity), can be used to identify families of elements with similar properties.elements with similar properties.

DOK 2DOK 2

Why is the Periodic Table Why is the Periodic Table important to me?important to me?

The periodic table is The periodic table is the most useful tool to the most useful tool to a chemist.a chemist.

You get to use it on You get to use it on every test.every test.

It organizes lots of It organizes lots of information about all information about all the known elements.the known elements.

Pre-Periodic Table Chemistry …Pre-Periodic Table Chemistry …

……was a mess!!!was a mess!!! No organization of No organization of

elements.elements. Imagine going to a Imagine going to a

grocery store with no grocery store with no organization!!organization!!

Difficult to find Difficult to find information.information.

Chemistry didn’t make Chemistry didn’t make sense.sense.

Dmitri Mendeleev: Father of the Dmitri Mendeleev: Father of the TableTable

HOW HIS HOW HIS WORKED…WORKED…

Put elements in rows Put elements in rows by increasing atomic by increasing atomic mass.mass.

Put elements in Put elements in columns by the way columns by the way they reacted.they reacted.

SOME PROBLEMS…SOME PROBLEMS… He left blank spaces He left blank spaces

for what he said were for what he said were undiscovered undiscovered elements. (Turned elements. (Turned out he was right!)out he was right!)

He broke the pattern He broke the pattern of increasing atomic of increasing atomic mass to keep similar mass to keep similar reacting elements reacting elements together.together.

The Current Periodic TableThe Current Periodic Table

Mendeleev wasn’t too far off.Mendeleev wasn’t too far off.Now the elements are put in rows by Now the elements are put in rows by

increasing increasing ATOMIC ATOMIC NUMBER!!NUMBER!!

The horizontal rows are called periods and The horizontal rows are called periods and are labeled from 1 to 7.are labeled from 1 to 7.

The vertical columns are called groups are The vertical columns are called groups are labeled from 1 to 18.labeled from 1 to 18.

GroupsGroups Vertical columns Vertical columns of elements of elements

in the periodic table.in the periodic table. Also known as Also known as FamiliesFamilies. .

Families may be one column, Families may be one column, or several columns put or several columns put together.together.

The elements in each group or The elements in each group or family, have family, have similar similar characteristicscharacteristics. .

Families have Families have namesnames rather rather than numbers. (Just like your than numbers. (Just like your family has a common last family has a common last name.)name.)

Groups…Here’s Where the Groups…Here’s Where the Periodic Table Gets Useful!!Periodic Table Gets Useful!!

Elements in the Elements in the same group same group have similar have similar chemical and chemical and physical physical properties!! properties!!

(Mendeleev did that on (Mendeleev did that on purpose.)purpose.)

Why??• They have the same

number of valence electrons.

• They will form the same kinds of ions.

HydrogenHydrogen

Hydrogen belongs to a Hydrogen belongs to a family of its own.family of its own.

Hydrogen is a diatomic, Hydrogen is a diatomic, reactive gas.reactive gas.

Hydrogen was involved in Hydrogen was involved in the explosion of the the explosion of the Hindenberg.Hindenberg.

Hydrogen is promising as Hydrogen is promising as an alternative fuel source an alternative fuel source for automobilesfor automobiles

Alkali MetalsAlkali Metals

11stst column on the column on the periodic table (Group periodic table (Group 1) not including 1) not including hydrogen. hydrogen.

Very reactive metals, Very reactive metals, always combined with always combined with something else in something else in nature (like in salt).nature (like in salt).

Soft enough to cut Soft enough to cut with a butter knifewith a butter knife

Alkaline Earth MetalsAlkaline Earth Metals Second column on Second column on

the periodic table. the periodic table. (Group 2)(Group 2)

Reactive metals that Reactive metals that are always combined are always combined with nonmetals in with nonmetals in nature.nature.

Several of these Several of these elements are elements are important mineral important mineral nutrients (such as Mg nutrients (such as Mg and Caand Ca

Transition MetalsTransition Metals

Elements in groups Elements in groups 3-123-12

Less reactive harder Less reactive harder metalsmetals

Includes metals Includes metals used in jewelry and used in jewelry and construction.construction.

Metals used “as Metals used “as metal.”metal.”

Conduct heat & Conduct heat & electricity. (ductile)electricity. (ductile)

Synthetic ElementsSynthetic ElementsMan-made – Man-made –

elements greater elements greater than atomic #92than atomic #92

Example - Example - promethium (61)promethium (61)

Some radioactiveSome radioactiveUsed in medical Used in medical

diagnosis & diagnosis & treatmenttreatment

NonmetalsNonmetals Some elements in groups 13-16 & Some elements in groups 13-16 &

all the elements of group 17 & 18 all the elements of group 17 & 18 & hydrogen.& hydrogen.

Nonmetals have a sub groups Nonmetals have a sub groups called:called:

HydrogenHydrogen Other NonmetalsOther Nonmetals

Chalogens (Stinky family)Chalogens (Stinky family)SemiconductorsSemiconductors

HalogensHalogens Noble GasesNoble Gases

Oxygen Family or ChalcogensOxygen Family or Chalcogens

Oxygen, SulfurOxygen, Sulfur Oxygen is necessary Oxygen is necessary

for respiration.for respiration. Many things that Many things that

stink, contain sulfur stink, contain sulfur (rotten eggs, garlic, (rotten eggs, garlic, skunks, etc.) skunks, etc.)

Semiconductors/MetalloidsSemiconductors/Metalloids Element – Carbon, Silicon, Element – Carbon, Silicon,

GermainiumGermainiumUsually found as graphite (lead Usually found as graphite (lead

used in pencils)used in pencils)DiamondsDiamondsMajor component of living and Major component of living and

nonliving organismsnonliving organismsSilicon is the most abundant Silicon is the most abundant

element compound in the Earth’s element compound in the Earth’s crust – used in computers, find it crust – used in computers, find it in sandin sand

Nitrogen FamilyNitrogen Family Elements in group 15Elements in group 15 Nitrogen makes up over Nitrogen makes up over

¾ of the atmosphere.¾ of the atmosphere. Nitrogen and Nitrogen and

phosphorus are both phosphorus are both important in living important in living things.things.

Most of the world’s Most of the world’s nitrogen is not available nitrogen is not available to living things.to living things.

The red stuff on the tip The red stuff on the tip of matches is of matches is phosphorus.phosphorus.

HalogensHalogens

Elements in group 17Elements in group 17 Very reactive, volatile, Very reactive, volatile,

diatomic, nonmetalsdiatomic, nonmetals Always found Always found

combined with other combined with other element in nature .element in nature .

Used as disinfectants Used as disinfectants and to strengthen and to strengthen teeth.teeth.

The Noble GasesThe Noble Gases

The Noble GasesThe Noble Gases

Elements in group 18Elements in group 18 VERY unreactive, monatomic VERY unreactive, monatomic

gases (inert)gases (inert) Used in lighted “neon” signsUsed in lighted “neon” signs Used in blimps to fix the Used in blimps to fix the

Hindenberg problem.Hindenberg problem. Have a full valence shell. Have a full valence shell. Exists as single atoms not Exists as single atoms not

molecules.molecules.

Name: Nelda Neutron

Description:Neutral

Favorite Activity:Hanging out at the Nucleus Arcade

In the center of Matterville, there is a place called the Nucleus Arcade, where two members of the Atoms Family like to hang out. Perky Patty Proton, like her sisters, is quite large with a huge smile and eyes that sparkle (+). Patty is always happy and has a very positive personality. Nerdy Nelda Neutron is large like Patty, but she has a boring, flat mouth and eyes with zero expression (o). Her family is very apathetic and neutral about everything. Patty, Nelda, and their sisters spend all their time at the arcade.

The Atoms Family Story

Name: Patty Proton

Description:Positive

Favorite Activity:Hanging out at the Nucleus Arcade

Name: Elliott Electron

Description:Negative

Favorite Activity:Racing around the arcade

Around the Nucleus Arcade, you will find a series of roadways that are used by another member of the Atoms Family, Enraged Elliott Electron. Elliott races madly around the Arcade on his bright red chrome-plated Harley-Davidson. He rides so fast that no one can be sure where he is at any time. Elliott is much smaller than Patty and Nelda and he is always angry because these bigger relatives will not let him in the Arcade. He has a frown on his face, eyes that are squinted with anger, and a very negative (-) attitude.

The morale of Matterville is stable as long as each negative Electron brother is balanced out by one positive Proton sister. The number of residents in Matterville depends on the Proton and Neutron families.

Challenge: What would happen to the morale of Matterville if one Elliott Electron was kidnapped?

The first energy street can only hold only two Electron brothers. The second and third energy streets, called the Energy Freeway, can hold 8 brothers. The fourth energy street, called the Energy Superhighway, can hold 18 of the brothers.

Nucleus ArcadeContains protons & neutrons

Energy Freeway Can hold 8 electrons

Energy Superhighway Can hold 18 electrons

Energy Street Can hold 2 electrons

Energy Freeway Can hold 8 electrons

Valence ElectronsValence Electrons

Electrons that are involved in transfer or Electrons that are involved in transfer or sharing. sharing.

The number of valence electrons an The number of valence electrons an element has increases from left to right element has increases from left to right across a period. across a period.

Atomic number equals the number of ____________

Atomic mass equals the number of ______________ + __________

The Atoms Family - Atomic Math Challenge

Atomic NumberSymbolNameAtomic Mass

protons

protons neutrons

Assignment: Finish the rest of the worksheet and turn it in to your teacher.

““Electron Cloud”Electron Cloud”

Electrons are arranged around the Electrons are arranged around the Nucleus in SHELLS. For simplicity they Nucleus in SHELLS. For simplicity they can be thought of like mini-planets orbiting can be thought of like mini-planets orbiting a central sun, but it is closer to the truth to a central sun, but it is closer to the truth to think of them as "clouds" of electric charge think of them as "clouds" of electric charge around the Nucleus.around the Nucleus.

Electron Dot DiagramsElectron Dot Diagrams

Examine the Electron Dot Diagram above – write at least 3 observations about the periodic table’s arrangement and how the arrangement compares to the number of dots it has beside it. Use the sciencesaurus book to help you write your observations page 265. Read page 268 – write 2 facts

How to write and Electron Dot DiagramHow to write and Electron Dot Diagram

1.1. Write the symbol of the element. Write the symbol of the element. (Each side of the letter represents (Each side of the letter represents an electron orbital.)an electron orbital.)

2.2. Find the # of electrons in the Find the # of electrons in the valence shell (the outermost valence shell (the outermost shell).shell).

3.3. The dots representing the The dots representing the electrons in the valence shell are electrons in the valence shell are placed around the symbol placed around the symbol beginning with the right side of the beginning with the right side of the letter.letter.

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