The Chemist’s Shorthand: Atomic Symbols - Element Symbols - Neon - Ne - Chlorine - Cl - Nitrogen -N-N-N-N

The Chemist’s Shorthand: The Chemist’s Shorthand: Atomic SymbolsAtomic Symbols


- Element SymbolsElement Symbols- Neon Neon - NeNe- ChlorineChlorine- ClCl- NitrogenNitrogen- NN



- OxygenOxygen- OO- SiliconSilicon- SiSi- ZincZinc- ZnZn



- GoldGold- AuAu- LeadLead- PbPb- SodiumSodium- NaNa- IronIron- FeFe

The Chemists’ Shorthand:The Chemists’ Shorthand:FormulasFormulas


Chemical Formula:Chemical Formula:

SymbolsSymbols = types of atoms = types of atoms

SubscriptsSubscripts = relative numbers of atoms = relative numbers of atoms

COCO22

Structural Formula:Structural Formula:

Individual bonds are shown Individual bonds are shown by linesby lines..

OO==CC==OO



A molecule contains four phosphorus A molecule contains four phosphorus atoms and ten oxygen atoms.atoms and ten oxygen atoms.

PP44OO1010

A molecule contains one aluminum atom A molecule contains one aluminum atom and three chlorine atoms.and three chlorine atoms.

AlClAlCl33

The Mass and Change of the The Mass and Change of the Electron, Proton, and NeutronElectron, Proton, and NeutronThe Mass and Change of the The Mass and Change of the Electron, Proton, and NeutronElectron, Proton, and Neutron

Particle Mass (kg) Charge

Electron 9.11 10 31 1

Proton 1.67 10 27 1+

Neutron 1.67 10 27 0

The Chemists’ Shorthand: Atomic The Chemists’ Shorthand: Atomic SymbolsSymbols

The Chemists’ Shorthand: Atomic The Chemists’ Shorthand: Atomic SymbolsSymbols

K Element Symbol39

19

Mass number

Atomic number

IsotopesIsotopesIsotopesIsotopes

Atoms with the same number of protons Atoms with the same number of protons but different numbers of neutrons.but different numbers of neutrons.

K-39 and K-40K-39 and K-40

Na-23 and Na-24Na-23 and Na-24

H-1, H-2, and H-3H-1, H-2, and H-3

Periodic TablePeriodic TablePeriodic TablePeriodic TableElements classified by:Elements classified by:

--propertiesproperties

-- atomic numberatomic number

GroupsGroups (vertical) (vertical)

1A = alkali metals1A = alkali metals

2A = alkaline earth metals2A = alkaline earth metals

7A = halogens7A = halogens

8A = noble gases8A = noble gases

PeriodsPeriods (horizontal) (horizontal)

Periodic TablePeriodic TablePeriodic TablePeriodic TableTransition metalsTransition metals

MetalsMetals

NonmetalsNonmetals

Semimetals (Metalloids)Semimetals (Metalloids)

IonsIonsIonsIons

CationCation: A positive ion: A positive ion

MgMg2+2+, NH, NH44++

AnionAnion: A negative ion: A negative ion

ClCl, SO, SO4422

IonsIonsIonsIons

MgMg2+2+

# of protons and electrons# of protons and electrons

12 protons and 10 electron12 protons and 10 electron

Mg -> MgMg -> Mg2+2+ + 2e + 2e--

Lost 2 electronsLost 2 electrons

IonsIonsIonsIons

KK++



K -> KK -> K++ + e + e--

Lost 1 electronLost 1 electron

IonsIonsIonsIons

ClCl



Cl + eCl + e-- -> Cl -> Cl--

Gained 1 electronGained 1 electron

IonsIonsIonsIons

OO



O + 2eO + 2e-- -> O -> O2-2-

Gained 2 electronsGained 2 electrons

Writing Formulas for Ionic Writing Formulas for Ionic CompoundsCompounds

Writing Formulas for Ionic Writing Formulas for Ionic CompoundsCompounds

1. Na1. Na++ and S and S2-2-

NaNa22SS

2. Ca2. Ca2+2+ and P and P3-3-

CaCa33PP22

Ionic Compounds: Net Charge of ZeroIonic Compounds: Net Charge of Zero

Naming CompoundsNaming CompoundsNaming CompoundsNaming Compounds

1. Cation first, then anion1. Cation first, then anion

2. Monatomic cation = name of the element2. Monatomic cation = name of the element

CaCa2+2+ = = calciumcalcium ionion

3. Monatomic anion = 3. Monatomic anion = rootroot + + -ide-ide

ClCl = = chlorchlorideide

CaClCaCl22 = = calcium chlorcalcium chlorideide

Binary Ionic Compounds:Binary Ionic Compounds:


NaClNaCl

sodium chloridesodium chloride

AlFAlF33

aluminum fluoridealuminum fluoride

MgBrMgBr22

magnesium bromidemagnesium bromide



-- When metal forms more than one When metal forms more than one cationcation

-- use use Roman numeral Roman numeral in namein name

PbClPbCl22

PbPb2+2+ is cationis cation

PbClPbCl22 = lead ( = lead (IIII) chloride) chloride



CuClCuCl

copper(I) chloridecopper(I) chloride

CuBrCuBr22

Copper(II) bromideCopper(II) bromide

FeFFeF33

iron(III) fluorideiron(III) fluoride



-- Compounds between two Compounds between two nonmetalsnonmetals

-- Second element Second element is named as if it were is named as if it were an an anionanion..

-- Use prefixesUse prefixes

-- Never use Never use mono- for the first element.mono- for the first element.

PP22OO55 = = didiphosphorus phosphorus pentpentoxideoxide

Binary molecular compounds:Binary molecular compounds:


PP22OO55

didiphosphorus phosphorus pentpentoxideoxide

CClCCl44

carboncarbon tetra tetrachloridechloride

Binary compounds:Binary compounds:


NN22OO33

didinitrogen nitrogen tritrioxideoxide

SClSCl66

sulfursulfur hexa hexachloridechloride

Binary compounds:Binary compounds:

Polyatomic Ions to MemorizePolyatomic Ions to MemorizePolyatomic Ions to MemorizePolyatomic Ions to Memorize

NONO33––

Nitrate ionNitrate ion

NONO22--

Nitrite ionNitrite ion


SOSO442-2-

Sulfate ionSulfate ion

SOSO332-2-

Sulfite ionSulfite ion


COCO332-2-

Carbonate ionCarbonate ion

HCOHCO33--

bicarbonate or hydrogen carbonate ionbicarbonate or hydrogen carbonate ion


POPO443-3-

Phosphate ionPhosphate ion


NHNH44++

Ammonium ionAmmonium ion

Compounds with Polyatomic Compounds with Polyatomic IonsIons


KK22SOSO44

potassium sulfatepotassium sulfate

NaNONaNO33

sodium nitratesodium nitrate



KK22COCO33

potassium carbonatepotassium carbonate

NaNa33POPO44

sodium phosphatesodium phosphate

Writing Formulas from NamesWriting Formulas from NamesWriting Formulas from NamesWriting Formulas from Names

Disulfur dichlorideDisulfur dichloride

SS22ClCl22

Potassium oxidePotassium oxide

KK22O O

calcium phosphatecalcium phosphate

CaCa33(PO(PO44))22

The MoleThe Mole

The number equal to the The number equal to the numbernumber of of carbon atoms in exactly 12 grams of pure carbon atoms in exactly 12 grams of pure 1212C.C.

1 mole 1 mole of anything = of anything = 6.022 6.022 10 102323 units of that thingunits of that thing

Avogadro’s number Avogadro’s number equalsequals

6.022 6.022 10 102323 units units

Molar MassMolar MassMolar MassMolar Mass

• A substance’s A substance’s molar massmolar mass (molecular weight) is the mass in grams of (molecular weight) is the mass in grams of one mole of the compound.one mole of the compound.

• COCO22 = 12.0107 + 2 x 15.9994 = 12.0107 + 2 x 15.9994

• = 44.0095 grams per mole= 44.0095 grams per mole

Molar MassMolar MassMolar MassMolar Mass

• How many moles of CaClHow many moles of CaCl22 are are

in a 10.0 g-sample of CaClin a 10.0 g-sample of CaCl22? The molar ? The molar

mass of CaClmass of CaCl22 is 110.98 g/mole. is 110.98 g/mole.

• Moles = mass x (1/molar mass)Moles = mass x (1/molar mass)• = 10.0 g x (1 mole / 110.98 g)= 10.0 g x (1 mole / 110.98 g)

• = 0.090106 = 0.090106 • = 0.0901 mole (3 sig figs)= 0.0901 mole (3 sig figs)

Molarity (Molarity (MM))Molarity (Molarity (MM))

• concentration expressed as concentration expressed as moles of solute per liter of solution.moles of solute per liter of solution.

• MM = moles of solute/L of solution = moles of solute/L of solution• Moles of solute = Molarity (Moles of solute = Molarity (MM) x L of ) x L of

solutionsolution• L of solution = moles of solute/Molarity (L of solution = moles of solute/Molarity (MM))

Molarity (Molarity (MM))Molarity (Molarity (MM))• Calculate the molarity of a solution Calculate the molarity of a solution

prepared by dissolving 65.5 g of solid NaCl in prepared by dissolving 65.5 g of solid NaCl in enough water to make 4.50 L of solution.enough water to make 4.50 L of solution.

• MM = moles of solute/L of solution = moles of solute/L of solution• Moles of NaCl = mass x (1/molar mass)Moles of NaCl = mass x (1/molar mass)

• Molar mass of NaCl = 22.989770 + 35.453 = Molar mass of NaCl = 22.989770 + 35.453 = 58.443 g/mole58.443 g/mole

• Moles of NaCl = 65.5 g x (1 mole/58.443 g ) Moles of NaCl = 65.5 g x (1 mole/58.443 g ) • = 1.12075 moles= 1.12075 moles

• Molarity = 1.12075 moles/4.50 L = 0.249 Molarity = 1.12075 moles/4.50 L = 0.249 MM

Chemical EquationsChemical Equations

Chemical change involves Chemical change involves a reorganization of the a reorganization of the atoms in one or more atoms in one or more substances.substances.

Chemical EquationChemical Equation

A representation of a chemical reaction:A representation of a chemical reaction:

CC22HH55OH (l) + OOH (l) + O22 (g) (g) COCO22 (g) (g) + H+ H22OO (g) (g)

CC22HH55OH (l) +3OOH (l) +3O22 (g) (g) 2CO2CO22 (g) (g) +3H+3H22OO (g) (g)

reactants reactants productsproducts

To Balance a Chemical To Balance a Chemical EquationEquation

Start with the Start with the most most complicated molecule.complicated molecule.

Use the Use the smallest integerssmallest integers for for the coefficients.the coefficients.

Never change the chemical Never change the chemical formula (subscripts)formula (subscripts)

Balance the following Chemical Balance the following Chemical EquationEquation

Li(s) + ClLi(s) + Cl22 (g) -> LiCl(s) (g) -> LiCl(s)

22Li(s) + ClLi(s) + Cl22 (g) -> (g) -> 22LiCl(s)LiCl(s)


Ca(s) + HCl (aq) -> CaClCa(s) + HCl (aq) -> CaCl22 (aq) + H (aq) + H22(g)(g)

Ca(s) + Ca(s) + 22HCl (aq) -> CaClHCl (aq) -> CaCl22 (aq) + H (aq) + H22(g)(g)


CC1212HH2222OO1111(s) + (s) + ____OO22(g) -> (g) ->

____COCO22(g) + (g) + ____HH22O(g)O(g)

CC1212HH2222OO1111(s) + (s) + 1212OO22(g) -> (g) ->

1212COCO22(g) + (g) + 1111HH22O(g) O(g)

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The Chemist’s Shorthand: Atomic Symbols - Element Symbols - Neon - Ne - Chlorine - Cl - Nitrogen -N-N-N-N