Bonding & The periodic Table. Structure of Matter All matter is formed from atoms. All matter is formed from atoms. If broken apart, almost all atoms

Bonding & The periodic Bonding & The periodic TableTable

Structure of MatterStructure of Matter

All matter is formed All matter is formed from atoms.from atoms.

If broken apart, almost If broken apart, almost all atoms contain all atoms contain three smaller particles three smaller particles called called protons, protons, neutrons, and neutrons, and electronselectrons..

Protons and neutrons Protons and neutrons cluster together in the cluster together in the atom’s center, called atom’s center, called the the nucleusnucleus..

Comparing AtomsComparing Atoms

The number of The number of protons protons determines an determines an element.element.

Atomic Structure & ForcesAtomic Structure & Forces 2 Main Regions of an Atom2 Main Regions of an Atom

Electron Cloud – Region of space around Electron Cloud – Region of space around the nucleus where electrons existthe nucleus where electrons exist

Electrons – Tiny negatively charged particle Electrons – Tiny negatively charged particle about 1,700 times smaller than a proton or about 1,700 times smaller than a proton or neutronneutron

Electrons are attracted to the positive charges Electrons are attracted to the positive charges in the nucleus in the nucleus

Electrons are organized into as many as seven Electrons are organized into as many as seven energy levels, depending on the number of energy levels, depending on the number of electronselectrons

Each energy level is broken into anywhere from 1 Each energy level is broken into anywhere from 1 to 7 orbitalsto 7 orbitals

Orbital – actual region of space where electrons Orbital – actual region of space where electrons exist; each orbital has a distinct shapeexist; each orbital has a distinct shape

Atomic Structure & Forces Atomic Structure & Forces

2 Main Regions of an Atom2 Main Regions of an Atom Nucleus – Very dense positively Nucleus – Very dense positively

charged center of the atomcharged center of the atom Makes up only 0.00000000000001% of Makes up only 0.00000000000001% of

volume of the atoms, but contains more volume of the atoms, but contains more than 99.9% of the mass.than 99.9% of the mass.

Composed of positively charged protons Composed of positively charged protons and neutral neutronsand neutral neutrons


Since protons are positively charged Since protons are positively charged and very close together, we should and very close together, we should expect an enormous repulsive force, expect an enormous repulsive force, that should break the nucleus apartthat should break the nucleus apart However, non-radioactive elements have However, non-radioactive elements have

very stable nuclei that have not changed very stable nuclei that have not changed since shortly after the formation of the since shortly after the formation of the universeuniverse

There must be some other attractive There must be some other attractive force in the nucleusforce in the nucleus


Strong Nuclear ForceStrong Nuclear Force Attractive force between any two Attractive force between any two

nuclear particles (protons, neutrons)nuclear particles (protons, neutrons) Only acts over a very short distanceOnly acts over a very short distance Overcomes the repulsive force Overcomes the repulsive force

between the positive protonsbetween the positive protons The Role of NeutronsThe Role of Neutrons

Neutrons make the nucleus more Neutrons make the nucleus more stable by adding to the strong nuclear stable by adding to the strong nuclear force, without adding positive, force, without adding positive, repulsive chargesrepulsive charges

Chemical and Physical Chemical and Physical PropertiesProperties

Physical Property – defines the physical Physical Property – defines the physical state of a materialstate of a material Temperature, color, shape, mass, volume, Temperature, color, shape, mass, volume,

weight, texture, structure, etc.weight, texture, structure, etc. Physical Changes – Any change that Physical Changes – Any change that

does not affect the identity of the atoms does not affect the identity of the atoms or molecules in the materialor molecules in the material Bending, Phase changes, breaking, heating, Bending, Phase changes, breaking, heating,

etcetc

Chemical and Physical Chemical and Physical PropertiesProperties

Chemical Properties – define the Chemical Properties – define the chemical reactivity of a substancechemical reactivity of a substance Ex: Reacts violently with water, Ex: Reacts violently with water,

decomposes in oxygen, etcdecomposes in oxygen, etc Chemical Changes – results in the Chemical Changes – results in the

formation of new molecules as atoms formation of new molecules as atoms are rearrangedare rearranged

Indicators of a Possible Indicators of a Possible Chemical ChangeChemical Change

Formation of a Precipitate – insoluble solidFormation of a Precipitate – insoluble solid Exothermic Reaction - Increase in temperature Exothermic Reaction - Increase in temperature Formation of a gas without heatingFormation of a gas without heating Endothermic Reaction - Decrease in Endothermic Reaction - Decrease in

temperature temperature Change in colorChange in color Evolution of Light without heatingEvolution of Light without heating Change in smellChange in smell Change in tasteChange in taste

Chemical or Physical Chemical or Physical Change?Change?

Leaf Changing ColorsLeaf Changing Colors ChemicalChemical

Tarnishing SilverTarnishing Silver ChemicalChemical

Burning CaloriesBurning Calories ChemicalChemical

Glass BreakingGlass Breaking PhysicalPhysical

Egg FryingEgg Frying ChemicalChemical

Wax BurningWax Burning ChemicalChemical

Wax MeltingWax Melting PhysicalPhysical

Water FreezingWater Freezing PhysicalPhysical

Wind BlowingWind Blowing PhysicalPhysical

Bomb ExplodingBomb Exploding ChemicalChemical

Indicate whether each of the following is a chemical or Indicate whether each of the following is a chemical or physical change.physical change.

Periodic tablePeriodic table

The The chemical chemical symbolsymbol is an is an abbreviation of the abbreviation of the element’s name.element’s name.

The The atomic numberatomic number is the number of is the number of protons all atoms protons all atoms of that element of that element have in their nuclei.have in their nuclei.

The Periodic Table of ElementsThe Periodic Table of Elements

The symbols for The symbols for some elements some elements don’t always don’t always obviously match obviously match their names.their names.

IsotopesIsotopes

Isotopes are atoms of the same Isotopes are atoms of the same element that have different element that have different numbers of neutrons.numbers of neutrons.

These are all isotopes of These are all isotopes of hydrogen.hydrogen.

IsotopesIsotopes

Structure of the Periodic Structure of the Periodic TableTable

Atomic number – number of protons (& Atomic number – number of protons (& in a neutral atom- the # of electrons)in a neutral atom- the # of electrons) The number of protons defines the identity The number of protons defines the identity

of the atomof the atom Atomic Mass – Average mass of protons Atomic Mass – Average mass of protons

and neutrons combined. atomic mass and neutrons combined. atomic mass units (amu)units (amu)

The The atomic massatomic mass is the average mass of is the average mass of all the known isotopes of the element.all the known isotopes of the element.

Oxidation Number – charge of the atom Oxidation Number – charge of the atom based on whether the atom needs to based on whether the atom needs to lose or gain electrons to become stable.lose or gain electrons to become stable.

Mass NumberMass Number

The total number of protons and The total number of protons and neutrons in the nucleus of an neutrons in the nucleus of an atom is called the mass number.atom is called the mass number.

The The mass numbermass number of an element is the of an element is the total number of protons and neutrons total number of protons and neutrons in the nucleus.in the nucleus.

Mass NumberMass Number


The Periodic Table is organized into The Periodic Table is organized into 18 columns and 7 rows18 columns and 7 rows The rows are called periodsThe rows are called periods The columns are called Families or The columns are called Families or

GroupsGroups Elements in the same Family or Group have Elements in the same Family or Group have

similar propertiessimilar properties

Elements that are part Elements that are part

of the same of the same groupgroup act alike. act alike. Dimitri MendeleevDimitri Mendeleev (1834- 1907) (1834- 1907)

organized information about all the organized information about all the known elements in a table that known elements in a table that visually organized the similarities visually organized the similarities between them.between them.

Mendeleev placed each element on Mendeleev placed each element on the table in a certain row and the table in a certain row and column based on its column based on its properties.properties.


11stst Alkali Metals Alkali Metals 22ndnd Alkaline Earth Metals Alkaline Earth Metals 1717thth Halogens Halogens 1818thth Noble Gasses Noble Gasses 33rdrd -12 -12thth Transition Metals Transition Metals


Stair Stepper = METALLOIDSStair Stepper = METALLOIDS The two rows at the bottom actually The two rows at the bottom actually

fit inside the 6fit inside the 6thth and 7 and 7thth Periods, and Periods, and are known as Lanthanide & Actinide are known as Lanthanide & Actinide SeriesSeries

Metals are to the left, Non-metals to Metals are to the left, Non-metals to the right of the stair stepperthe right of the stair stepper


The Periodic Table also tells us The Periodic Table also tells us about the electron structure of an about the electron structure of an atomatom The PERIOD number represents the The PERIOD number represents the

energy level of the electronsenergy level of the electrons The GROUP number represents the The GROUP number represents the

number of electrons in the outer number of electrons in the outer energy levelenergy level

Ex: Na is in a Group 1 element, therefore Ex: Na is in a Group 1 element, therefore it has one electron in the outer energy it has one electron in the outer energy levellevel

The Role of Electrons in The Role of Electrons in BondingBonding

The sharing or transfer of electrons is what The sharing or transfer of electrons is what holds atoms together in a molecule or holds atoms together in a molecule or compoundcompound Typically, only the electrons in the outer energy Typically, only the electrons in the outer energy

level are used for bonding.level are used for bonding. This means that an atom’s chemical reactivity is This means that an atom’s chemical reactivity is

defined by the number of electrons in its outer energy defined by the number of electrons in its outer energy levellevel

OROR how badly the element wants to lose or gain how badly the element wants to lose or gain electronselectrons

Valence Electrons Valence Electrons outer shell electrons in “s” & “p” columns (total 8 to be stable)

The outer energy level is called the The outer energy level is called the Valence ShellValence Shell

The Role of Electrons in The Role of Electrons in BondingBonding

Octet RuleOctet Rule all elements want 8 valence shell electrons (Noble Gas Wannabe’s) In addition, all atoms want to have a full In addition, all atoms want to have a full

valence shell (8 valence electrons)valence shell (8 valence electrons) Atoms react with one another in an attempt to Atoms react with one another in an attempt to

gain or lose electrons to fill their valence shellgain or lose electrons to fill their valence shell During a reaction, electrons can be shared or During a reaction, electrons can be shared or

completely transferredcompletely transferred

Comprehension CheckComprehension Check

How many valence electrons does How many valence electrons does phosphorus have? phosphorus have? 55

How many electrons does How many electrons does phosphorus have to gain or lose in phosphorus have to gain or lose in order to fill its valence shell?order to fill its valence shell? Lose 5, Gain 3Lose 5, Gain 3

PWYR – Valence PWYR – Valence SchmalenceSchmalence

tintin 44

arsenicarsenic 55

strontiumstrontium 22

brominebromine 77

sodiumsodium 11

telluriumtellurium 66

galliumgallium 33

kryptonkrypton 88

PWYR - To Gain or Not to GainPWYR - To Gain or Not to Gain

nitrogennitrogen Gain 3Gain 3

berylliumberyllium Lose 2Lose 2

xenonxenon NoneNone

carbon carbon Gain/Lose 4Gain/Lose 4

oxygenoxygen Gain 2Gain 2

lithiumlithium Lose 1Lose 1

chlorinechlorine Gain 1Gain 1

boronboron Lose 3Lose 3

Types of BondsTypes of Bonds

2 Main Types of Chemical Bonds2 Main Types of Chemical Bonds Ionic Bonds – Results from the complete Ionic Bonds – Results from the complete

transfer of electrons (metal & Non metal)transfer of electrons (metal & Non metal) Ions:Ions: charged particle or atom (b/c lost or

gained electrons) Cation loses electrons and is positive Anion gains electrons and is negative

Covalent Bonds – Results from the Covalent Bonds – Results from the sharing of electrons (non metal & non sharing of electrons (non metal & non metal----tug-o-war)metal----tug-o-war)

Oxidation NumbersOxidation Numbers

Oxidation Numbers tell us how Oxidation Numbers tell us how many electrons an atom loses or many electrons an atom loses or gainsgains Positive oxidation= atom lost Positive oxidation= atom lost

electronselectrons Negative oxidation= numbers atom Negative oxidation= numbers atom

gained electronsgained electrons Some atoms have more than one Some atoms have more than one

possibility (transition metals—look to possibility (transition metals—look to the non metal to find charge)the non metal to find charge)

Predicting BondingPredicting Bonding

We can predict which atoms will We can predict which atoms will bond based on their oxidation bond based on their oxidation numbersnumbers Ex 1: Na has a +1 Oxidation Number; it Ex 1: Na has a +1 Oxidation Number; it

wants to lose one electron; Cl has a -1 wants to lose one electron; Cl has a -1 Oxidation Number; it wants to gain one Oxidation Number; it wants to gain one electron electron

These atoms will react quickly an violently in These atoms will react quickly an violently in a 1:1 ratio to give NaCla 1:1 ratio to give NaCl

Predicting BondingPredicting Bonding

We can predict which atoms will bond We can predict which atoms will bond based on their oxidation numbersbased on their oxidation numbers Ex 2: Ca has a +2 Oxidation Number; it Ex 2: Ca has a +2 Oxidation Number; it

wants to lose two electron; F has a -1 wants to lose two electron; F has a -1 Oxidation Number; it wants to gain one Oxidation Number; it wants to gain one electron electron

Ca will give one of its valence electrons to Ca will give one of its valence electrons to one F and the second electron to a second F, one F and the second electron to a second F, giving CaFgiving CaF22

Comprehension CheckComprehension Check

What compound is formed when What compound is formed when Ba reacts with Br?Ba reacts with Br? BaBrBaBr22

What compound is formed when What compound is formed when Be reacts with O?Be reacts with O? BeOBeO

What compound is formed when Al What compound is formed when Al reacts with I?reacts with I? AlIAlI33

PWYR – Family Bonds 1 of 2PWYR – Family Bonds 1 of 2

sodium, chlorinesodium, chlorine NaClNaCl

calcium oxygencalcium oxygen CaOCaO

gallium, gallium, phosphorusphosphorus GaPGaP

carbon, berylliumcarbon, beryllium BeBe44CC22

aluminum, chlorinealuminum, chlorine AlClAlCl33

sodium, phosphorussodium, phosphorus NaNa33PP

barium, chlorinebarium, chlorine BaClBaCl22

strontium, nitrogenstrontium, nitrogen SrSr33NN22

PWYR – Family Bonds 2 of 2PWYR – Family Bonds 2 of 2

When Groups I and VII elements When Groups I and VII elements bond what is the ratio of the atoms?bond what is the ratio of the atoms? 1:11:1

When Groups II and V elements bond When Groups II and V elements bond what is the ratio of the atoms?what is the ratio of the atoms? 3:23:2

When Groups III and IV elements When Groups III and IV elements bond what is the ratio of the atoms?bond what is the ratio of the atoms? 4:34:3

Metals & Oxidation NumbersMetals & Oxidation Numbers

When metals with multiple oxidation When metals with multiple oxidation numbers bond to non-metals, more numbers bond to non-metals, more than one compound is formed.than one compound is formed. Since all the metals (except antimony and Since all the metals (except antimony and

rhenium) are positive, the non-metals rhenium) are positive, the non-metals must use their negative oxidation must use their negative oxidation number.number.

Ex: molybdenum and oxygenEx: molybdenum and oxygen MoO, MoMoO, Mo22OO33, Mo, Mo22OO44, Mo, Mo22OO55, MoO, MoO33

PWYR – Oh the PossibilitiesPWYR – Oh the Possibilities

titanium and chlorinetitanium and chlorine TiClTiCl33, TiCl, TiCl44

thallium and phosphorusthallium and phosphorus TlTl33P, TlPP, TlP

tantalum and oxygentantalum and oxygen TaTa22OO55

ruthenium and carbonruthenium and carbon RuRu22C, RuC, Ru44CC33, RuC, Ru, RuC, Ru22CC33, RuC, RuC22, ,

Non-metals & Oxidation Non-metals & Oxidation NumbersNumbers

Atoms with multiple oxidation Atoms with multiple oxidation numbers can react to form multiple numbers can react to form multiple compounds depending on which compounds depending on which oxidation numbers they chose.oxidation numbers they chose. Ex: If bromine and nitrogen reacted, one Ex: If bromine and nitrogen reacted, one

would have to be positive (lose ewould have to be positive (lose e--) and ) and the other negative (gain ethe other negative (gain e--).).

Let’s assume bromine takes its -1 Let’s assume bromine takes its -1 oxidation number, nitrogen can be 2, 3, oxidation number, nitrogen can be 2, 3, 4, or 54, or 5

NBrNBr22, NBr, NBr33, NBr, NBr44, NBr, NBr55

Non-metals & Oxidation Non-metals & Oxidation NumbersNumbers

If nitrogen takes its negative three If nitrogen takes its negative three oxidation number bromine can be 1 or oxidation number bromine can be 1 or 5.5. NBrNBr33, N, N55BrBr33

PWYR – It Gets WorsePWYR – It Gets Worse

Selenium and oxygenSelenium and oxygen SeOSeO22, SeO, SeO33

Phosphorus and fluorinePhosphorus and fluorine PFPF33, PF, PF44, PF, PF55

Tellurium and iodineTellurium and iodine TeITeI22, Te, Te55II22, Te, Te77II22, TeI, TeI44, TeI, TeI66

Nitrogen and chlorineNitrogen and chlorine NClNCl22, NCl, NCl33, NCl, NCl44, NCl, NCl55, NCl, N, NCl, N55ClCl33, N, N77ClCl33

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Bonding & The periodic Table. Structure of Matter All matter is formed from atoms. All matter is formed from atoms. If broken apart, almost all atoms