Atoms, Ions and Molecules

Atoms, Ions and Atoms, Ions and MoleculesMolecules

Chapter 2Chapter 2

Dalton’s Atomic Theory Dalton’s Atomic Theory (1808)(1808)

Atoms cannot be subdivided, created, or destroyed Atoms of different elements combine in simple whole-number ratios to form chemical compounds In chemical reactions, atoms are combined, separated, or rearranged

All matter is composed of extremely small particles called atoms Atoms of a given element are identical in size, mass, and other properties; atoms of different elements differ in size, mass, and other properties

John Dalton

Atomic Theory of MatterAtomic Theory of Matter

All All mattermatter is made of tiny is made of tiny indivisibleindivisible particles called atoms.particles called atoms.

This proposal has been verified This proposal has been verified experimentally. Single atoms of a variety of experimentally. Single atoms of a variety of elements have been photographed with a elements have been photographed with a scanning transmission electron microscope.scanning transmission electron microscope.


2. Atoms of the same element are 2. Atoms of the same element are identical and atoms of a different identical and atoms of a different element have different masses and element have different masses and chemical properties.chemical properties.

However you will learn that atoms of the However you will learn that atoms of the same element can have different masses.same element can have different masses.


Atoms of different elements combine in Atoms of different elements combine in whole number ratios to form whole number ratios to form compoundscompounds

One molecule of water always consists of One molecule of water always consists of two atoms of hydrogen and one atom of two atoms of hydrogen and one atom of oxygen.oxygen.


4. Chemical reactions involve the 4. Chemical reactions involve the rearrangement of atoms. No new atoms rearrangement of atoms. No new atoms are created or destroyed.are created or destroyed.

Modern research has altered this proposal. Modern research has altered this proposal. Atoms are not indestructible and may lose Atoms are not indestructible and may lose their identity when split during nuclear their identity when split during nuclear reactions. However Dalton’s proposal reactions. However Dalton’s proposal remains true, for chemical reactions.remains true, for chemical reactions.

Law of Multiple ProportionsLaw of Multiple Proportions

Atoms of two or more elements may combine in Atoms of two or more elements may combine in different ratios to produce more than one different ratios to produce more than one compound.compound.

A compound always contains two or more A compound always contains two or more elements combined in a definite elements combined in a definite proportion by mass.proportion by mass.

Law of Constant CompositionLaw of Constant Composition

Law of Conservation of MassLaw of Conservation of Mass

The total mass of materials present after a The total mass of materials present after a chemical reaction is the same as the total chemical reaction is the same as the total mass before the reactionmass before the reaction

This is the basis for which postulate?This is the basis for which postulate?

Parts of an AtomParts of an Atom

J. J. Thomson - English physicist. 1897J. J. Thomson - English physicist. 1897

Made a piece of equipment called a cathode Made a piece of equipment called a cathode ray tube.ray tube.

Determined the charge to mass ratioDetermined the charge to mass ratio

It is a vacuum tube - all the air has been It is a vacuum tube - all the air has been pumped out.pumped out.

Thomson’s ExperimentThomson’s Experiment

Voltage source

- +

Vacuum tube

Metal Disks

Thomson ExperimentThomson Experiment

Voltage source

Passing an electric current makes a beam Passing an electric current makes a beam appear to move from the negative to the appear to move from the negative to the positive endpositive end

- +


Voltage source

+

-

By adding an electric field By adding an electric field


Voltage source

+

-By adding an electric field he found that By adding an electric field he found that the moving pieces were negative the moving pieces were negative

What Did Thomson What Did Thomson Demonstrate?Demonstrate?

Cathode rays:Cathode rays:

Travel in straight linesTravel in straight lines

Are negatively chargedAre negatively charged

Are deflected by electric and magnetic fieldsAre deflected by electric and magnetic fields

Thomson’s ModelThomson’s Model

Found the electronFound the electron

Said the atom was Said the atom was like plum puddinglike plum pudding

A bunch of positive A bunch of positive stuff, with the stuff, with the electrons able to be electrons able to be removedremoved

Robert MillikanRobert Millikan

American ScientistAmerican Scientist

GoalGoal: Determine the charge on the : Determine the charge on the electron to determine its masselectron to determine its mass

Chapter 2Chapter 2

The Discovery of The Discovery of Atomic StructureAtomic Structure

Cathode Rays and ElectronsConsider the following experiment:• Oil drops are sprayed above a positively charged

plate containing a small hole. • As the oil drops fall through the hole, they are given

a negative charge.• Gravity forces the drops downward. The applied

electric field forces the drops upward.• When a drop is perfectly balanced, the weight of the

drop is equal to the electrostatic force of attraction between the drop and the positive plate.

Millikan’s Experiment

Oil

Atomizer

Oil droplets

Telescope

-

+

Millikan’s ExperimentMillikan’s Experiment

X-rays

X-rays give some drops a charge.

Millikan’s ExperimentMillikan’s Experiment

Some drops would hoverFrom the mass of the drop and the charge on the plates, he calculated the mass of an electron

RadioactivityRadioactivity

Discovered by accidentDiscovered by accidentFrench scientist Henri BequerelFrench scientist Henri Bequerel

Studying pitchblende (oxides of uranium)Studying pitchblende (oxides of uranium)Discovered that it spontaneously emits high energy Discovered that it spontaneously emits high energy radiationradiation

Three types Three types alpha- helium nucleus (+2 charge, large mass)alpha- helium nucleus (+2 charge, large mass) beta- high speed electronbeta- high speed electron gamma- high energy lightgamma- high energy light

(Uranium compound)2.2

Rutherford’s ExperimentRutherford’s Experiment

Ernest Rutherford English physicist. (1910)Ernest Rutherford English physicist. (1910)

Believed in the plum pudding model of the Believed in the plum pudding model of the atom.atom.

Used uranium to produce alpha particles.Used uranium to produce alpha particles.


Aimed alpha particles at gold foil by drilling Aimed alpha particles at gold foil by drilling hole in lead block.hole in lead block.

Since the mass is evenly distributed in gold Since the mass is evenly distributed in gold atoms alpha particles should go straight atoms alpha particles should go straight through.through.

Used gold foil because it could be made Used gold foil because it could be made atoms thin.atoms thin.


When the alpha particles hit a florescent When the alpha particles hit a florescent screen, it glows.screen, it glows.


Lead block

Uranium

Gold Foil

Florescent Screen

What he expected

Why ??Why ??

The alpha particles The alpha particles would pass through would pass through without changing without changing direction very muchdirection very much

The negative The negative charges were charges were spread out evenly. spread out evenly. Alone they were Alone they were not enough to stop not enough to stop the alpha particlesthe alpha particles

What he got

How He Explained ItHow He Explained It

Atom is mostly emptyAtom is mostly empty

Small dense, positive Small dense, positive piece at centerpiece at center

Alpha particles are Alpha particles are deflected by it if they deflected by it if they get close enoughget close enough

+

How He Explained ItHow He Explained It

Density and the AtomDensity and the Atom

Since most of the particles went through, it Since most of the particles went through, it was mostly empty.was mostly empty.

Because the pieces turned so much, the Because the pieces turned so much, the positive pieces were heavy.positive pieces were heavy.

Small volume, big mass, big densitySmall volume, big mass, big density

This small dense positive area is the This small dense positive area is the nucleusnucleus

Discovery of the NeutronDiscovery of the Neutron

James Chadwick bombarded beryllium-9 with alpha particles, carbon-12 atoms were formed, and neutrons were emitted.

n10

+He42

+Be94 C12

6

Dorin, Demmin, Gabel, Chemistry The Study of Matter 3rd Edition, page 764 *Walter Boethe

http://en.wikipedia.org/wiki/James_Chadwick

http://en.wikipedia.org/wiki/Walter_Bothe

Modern ViewModern View

The atom is mostly The atom is mostly empty spaceempty space

Two regionsTwo regions

Nucleus- protons and Nucleus- protons and neutronsneutrons

Electron cloud- region Electron cloud- region where you might find an where you might find an electronelectron

Structure of AtomStructure of Atom

There are two regions:There are two regions: The nucleus: with protons and neutrons The nucleus: with protons and neutrons

Almost all the massAlmost all the mass

Electron cloud- Most of the volume of an Electron cloud- Most of the volume of an atomatom

The region where the electron can be foundThe region where the electron can be found

Size of AtomSize of Atom

Atoms are small.Atoms are small.

Measured in picometers, 10Measured in picometers, 10-12-12 meters meters

Hydrogen atom, 32 pm radiusHydrogen atom, 32 pm radius

Size of AtomSize of Atom

Nucleus tiny compared to atomNucleus tiny compared to atom

IF the atom was the size of a stadium, IF the atom was the size of a stadium, the nucleus would be the size of a the nucleus would be the size of a marble.marble.

Radius of the nucleus near 10Radius of the nucleus near 10-15-15m.m.

Density near 10Density near 101414 g/cm g/cm33

Subatomic ParticlesSubatomic Particles

POSIT IVECHARG E

PROT ONS

NEUT RALCHARG E

NEUT RONS

NUCLEUS

NEG AT IVE CHARG E

ELECT RONS

AT OM

Most of the atom’s mass.

NUCLEUSNUCLEUS ELECTRONSELECTRONS

PROTONSPROTONS NEUTRONSNEUTRONS Negative Charge

PositiveCharge

NeutralCharge

ATOM

QUARKS equal in a neutral atom

Subatomic particlesSubatomic particles

Electron

Proton

Neutron

Name Symbol ChargeRelative mass

Actual mass (g)

e-

p+

no

-1

+1

0

1/1840

1

1

9.11 x 10-28

1.67 x 10-24

1.67 x 10-24

Atomic number (Z) = number of protons in nucleus

Mass number (A) = number of protons + number of neutrons

= atomic number (Z) + number of neutrons

Isotopes are atoms of the same element (X) with different numbers of neutrons in their nuclei

XAZ

H11 H (D)2

1 H (T)31

U23592 U238

92

Mass Number

Atomic NumberElement Symbol

SymbolsSymbols

Find the Find the number of protonsnumber of protons

number of number of neutronsneutrons

number of number of electronselectrons

Atomic numberAtomic number

Mass NumberMass Number

F19

9

SymbolsSymbols

Find the Find the

–number of protonsnumber of protons

–number of neutronsnumber of neutrons

–number of electronsnumber of electrons

–Atomic numberAtomic number

–Mass NumberMass Number

Br80 35

SymbolsSymbols

if an element has an atomic number of 34 if an element has an atomic number of 34 and a mass number of 78 what is the and a mass number of 78 what is the

number of protonsnumber of protons

number of neutronsnumber of neutrons

number of electronsnumber of electrons

Complete symbolComplete symbol

Atomic MassAtomic Mass

How heavy is an atom of oxygen?How heavy is an atom of oxygen?

There are different kinds of oxygen atoms.There are different kinds of oxygen atoms.

More concerned with average atomic mass.More concerned with average atomic mass.

Based on abundance of each element in Based on abundance of each element in nature.nature.

Don’t use grams because the numbers Don’t use grams because the numbers would be too smallwould be too small

Measuring Atomic MassMeasuring Atomic Mass

Unit is the Atomic Mass Unit (amu)Unit is the Atomic Mass Unit (amu)

One twelfth the mass of a carbon-12 One twelfth the mass of a carbon-12 atom. atom.

Each isotope has its own atomic mass Each isotope has its own atomic mass we need the average from percent we need the average from percent abundance.abundance.

Calculating averagesCalculating averages

You have five rocks, four with a mass of 50 You have five rocks, four with a mass of 50 g, and one with a mass of 60 g. What is the g, and one with a mass of 60 g. What is the average mass of the rocks?average mass of the rocks?

Total mass = 4 x 50 + 1 x 60 = 260 gTotal mass = 4 x 50 + 1 x 60 = 260 g

Average mass = 4 x 50 + 1 x 60 = 260 gAverage mass = 4 x 50 + 1 x 60 = 260 g 5 5 5 5

Calculating averagesCalculating averages

Average mass = 4 x 50 + 1 x 60 = 260 gAverage mass = 4 x 50 + 1 x 60 = 260 g 5 5 5 5 5 5

Average mass = .8 x 50 + .2 x 60Average mass = .8 x 50 + .2 x 60

80% of the rocks were 50 grams80% of the rocks were 50 grams

20% of the rocks were 60 grams20% of the rocks were 60 grams

Average = % as decimal x mass + Average = % as decimal x mass + % as decimal x mass + % as decimal x mass + % as decimal x mass + % as decimal x mass +


Calculate the atomic mass of copper if Calculate the atomic mass of copper if copper has two isotopes. 69.1% has a mass copper has two isotopes. 69.1% has a mass of 62.93 amu and the rest has a mass of of 62.93 amu and the rest has a mass of 64.93 amu.64.93 amu.

100

90

80

70

60

50

40

30

20

10

034 35 36 37

Ab

un

dan

ce

Mass

Mass spectrum of chlorine. Elemental chlorine (Cl2) contains only two isotopes: 34.97 amu (75.53%) and 36.97 (24.47%)

AAM = (34.97 amu)(0.7553) + (36.97 amu)(0.2447)

AAM = (26.412841 amu) + (9.046559 amu)

AAM = 35.4594 amu

Cl-35

Cl-37

Cl35.4594

17


Magnesium has three isotopes. 78.99% Magnesium has three isotopes. 78.99% magnesium 24 with a mass of 23.9850 amu, magnesium 24 with a mass of 23.9850 amu, 10.00% magnesium 25 with a mass of 24.9858 10.00% magnesium 25 with a mass of 24.9858 amu, and the rest magnesium 26 with a mass of amu, and the rest magnesium 26 with a mass of 25.9826 amu. What is the atomic mass of 25.9826 amu. What is the atomic mass of magnesium?magnesium?

If not told otherwise, the mass of the isotope is the If not told otherwise, the mass of the isotope is the mass number in amu mass number in amu

The Periodic TableThe Periodic Table

Period

Group

Alkali M

etal

Noble G

as

Halogen

Alkali E

arth Metal

2.4

Atoms and ionsAtoms and ions

Atoms are electrically neutral.Atoms are electrically neutral.

Same number of protons and electrons.Same number of protons and electrons.

Ions are atoms, or groups of atoms, Ions are atoms, or groups of atoms, with a charge.with a charge.

Atoms and IonsAtoms and Ions

Different numbers of protons and Different numbers of protons and electrons.electrons.

Only electrons can move.Only electrons can move.

Gain or lose electrons.Gain or lose electrons.

AnionAnion

A negative ion.A negative ion.

Has gained electrons.Has gained electrons.

Non metals can gain electrons.Non metals can gain electrons.

Charge is written as a super script on Charge is written as a super script on the right.the right.

F-1 Has gained one electron

O-2 Has gained two electrons

Cations

Positive ions. Formed by losing electrons. More protons than electrons. Metals form cations.

K+1 Has lost one electron

Ca+2 Has lost two electrons

Two Types of CompoundsTwo Types of Compounds

Molecular compoundsMolecular compounds

Made of molecules.Made of molecules.

Made by joining nonmetal atoms together Made by joining nonmetal atoms together into molecules.into molecules.


Ionic CompoundsIonic Compounds

Made of cations and anions.Made of cations and anions. Metals and nonmetals.Metals and nonmetals. The electrons lost by the cation are gained The electrons lost by the cation are gained

by the anion.by the anion. The cation and anions surround each The cation and anions surround each

other.other. Smallest piece is a FORMULA UNIT.Smallest piece is a FORMULA UNIT.


Smallest piece

Melting Point

State

Types of elements

Formula Unit Molecule

Metal and Nonmetal

Nonmetals

solidSolid, liquid or gas

High >300ºC Low <300ºC

Ionic Molecular

Chemical FormulasChemical Formulas

Shows the kind and number of atoms in Shows the kind and number of atoms in the smallest piece of a substance.the smallest piece of a substance.

Molecular formula- number and kinds of Molecular formula- number and kinds of atoms in a molecule.atoms in a molecule.

COCO22

Charges on ionsCharges on ions

For most of the Group A elements, the For most of the Group A elements, the Periodic Table can tell what kind of ion Periodic Table can tell what kind of ion they will form from their location.they will form from their location.

Elements in the same group have Elements in the same group have similar properties.similar properties.

Including the charge when they are Including the charge when they are ions.ions.

+2

+1

+3 -3 -2 -1

Naming ionsNaming ions

We will use the systematic way.We will use the systematic way.

Cation- if the charge is always the same Cation- if the charge is always the same (Group A) just write the name of the metal.(Group A) just write the name of the metal.

Transition metals can have more than one Transition metals can have more than one type of charge.type of charge. Indicate the charge with roman numerals in Indicate the charge with roman numerals in

parenthesis.parenthesis.

Name theseName these

NaNa+1+1

CaCa+2+2

AlAl+3+3

FeFe+3+3

FeFe+2+2

PbPb+2+2

LiLi+1+1

Write Formulas for theseWrite Formulas for these

Potassium ionPotassium ion

Magnesium ion Magnesium ion

Copper (II) ionCopper (II) ion

Chromium (VI) ionChromium (VI) ion

Barium ionBarium ion

Mercury (II) ionMercury (II) ion

Naming AnionsNaming Anions

Anions are always the same.Anions are always the same.

Change the element ending to – Change the element ending to – ideide

FF-1-1 Fluoride Fluoride


ClCl-1-1

NN-3-3

BrBr-1-1

OO-2-2

Write theseWrite these

Sulfide ionSulfide ion

iodide ioniodide ion

phosphide ionphosphide ion

Strontium ionStrontium ion

Polyatomic ionsPolyatomic ionsGroups of atoms that stay together and Groups of atoms that stay together and have a charge.have a charge.You must memorize these (table 2.5).You must memorize these (table 2.5). Acetate CAcetate C22HH33OO22

-1-1

Nitrate NONitrate NO33-1-1

Nitrite NONitrite NO22-1-1

Hydroxide OHHydroxide OH-1-1

Permanganate MnOPermanganate MnO44-1-1

Cyanide CNCyanide CN-1-1

Polyatomic ionsPolyatomic ions

Sulfate Sulfate SOSO44-2-2

Sulfite Sulfite SOSO33-2-2

Carbonate Carbonate COCO33-2-2

Chromate Chromate CrOCrO44-2-2

Dichromate Dichromate CrCr22OO77--

22

ChlorateChlorate ClOClO33--

Phosphate Phosphate POPO44-3-3

Phosphite Phosphite POPO33-3-3

Hydronium HHydronium H33OO + +

PerchloratePerchlorate

ClOClO44--

Ammonium Ammonium NHNH44+1+1

Chlorite ClOChlorite ClO2 2 --

Polyatomic IonsPolyatomic Ions

Hypochlorite ClOHypochlorite ClO--

Hydrogen carbonate ion HCOHydrogen carbonate ion HCO33--

Dihydrogen phosphate ion HDihydrogen phosphate ion H22POPO44--

Ions and Ionic Ions and Ionic CompoundsCompounds

Nomenclature - Nomenclature - HumorHumor

“Ferrous Wheel”

Fe = iron (Latin = ferrum)

Fe2+ = lower oxidation state = ferrousFe3+ = higher oxidation state = ferric

BaNa2

“BaNaNa”

Fe2+

Fe2+

Fe2+

Fe2+

Fe2+

Fe2+

Fe2+

Fe2+

What weapon can you make from the elements nickel, potassium and iron?

A KNiFe

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Naming Binary Ionic CompoundsNaming Binary Ionic Compounds

Binary Compounds - 2 elements.Binary Compounds - 2 elements.

Ionic - a cation and an anion.Ionic - a cation and an anion.

To write the names just name the two To write the names just name the two ions.ions.

Easy with Representative elements.Easy with Representative elements.

Group AGroup A

NaCl = NaNaCl = Na+ + ClCl-- = sodium chloride = sodium chloride

MgBrMgBr22 = Mg = Mg+2 +2 BrBr- - = magnesium bromide= magnesium bromide


The problem comes with the transition The problem comes with the transition metals.metals.

Need to figure out their charges.Need to figure out their charges.

The compound must be neutral.The compound must be neutral.

same number of + and – charges.same number of + and – charges.

Use the anion to determine the charge Use the anion to determine the charge on the positive ion.on the positive ion.


Write the name of CuOWrite the name of CuO

Need the charge of CuNeed the charge of Cu

O is -2O is -2

copper must be +2copper must be +2

Copper (II) oxideCopper (II) oxide

Name CoClName CoCl33

Cl is -1 and there are three of them = -3Cl is -1 and there are three of them = -3

Co must be +3 Cobalt (III) chlorideCo must be +3 Cobalt (III) chloride

Naming Binary Ionic Naming Binary Ionic CompoundsCompounds

Write the name of CuWrite the name of Cu22S.S.

Since S is -2, the CuSince S is -2, the Cu22 must be +2, so must be +2, so each one is +1.each one is +1.copper (I) sulfidecopper (I) sulfide

FeFe22OO33

Each O is -2 Each O is -2 Fe must be = + 3Fe must be = + 3iron (III) oxide iron (III) oxide


Write the names of the following:Write the names of the following:

KClKCl

NaNa33NN

CrNCrN

NaNa22SeSe

Ternary Ionic Compounds Ternary Ionic Compounds

Will have polyatomic ionsWill have polyatomic ions

At least three elementsAt least three elements

name the ionsname the ions

NaNONaNO33

CaSOCaSO44

CuSOCuSO33

(NH(NH44))22OO

Ternary Ionic CompoundsTernary Ionic Compounds

LiCNLiCN

Fe(OH)Fe(OH)33

(NH(NH44))22COCO33

NiPONiPO44

Writing FormulasWriting Formulas

The charges have to add up to zero.The charges have to add up to zero.

Get charges on pieces.Get charges on pieces.

Cations from name of table.Cations from name of table.

Anions from table or polyatomic.Anions from table or polyatomic.

Balance the charges by adding Balance the charges by adding subscripts.subscripts.

Put polyatomics in parenthesis.Put polyatomics in parenthesis.


Write the formula for calcium chloride.Write the formula for calcium chloride.

Calcium is CaCalcium is Ca+2+2

Chloride is ClChloride is Cl-1-1

CaCa+2+2 Cl Cl-1-1

CaClCaCl22

Write the formulas for theseWrite the formulas for theseLithium sulfideLithium sulfide

tin (II) oxidetin (II) oxide

tin (IV) oxidetin (IV) oxide

Magnesium fluorideMagnesium fluoride

Copper (II) sulfateCopper (II) sulfate

Iron (III) phosphideIron (III) phosphide

gallium nitrategallium nitrate

Iron (III) sulfideIron (III) sulfide

Write the formulas for theseWrite the formulas for these

Ammonium chlorideAmmonium chloride

ammonium sulfideammonium sulfide

barium nitratebarium nitrate

Things to look forThings to look for

If cations have (), the number is their If cations have (), the number is their charge.charge. Transition metalTransition metal

If anions end in If anions end in -ide-ide they are probably off they are probably off the periodic table (Monoatomic)the periodic table (Monoatomic)

If anion ends in If anion ends in -ate-ate or or -ite-ite it is it is polyatomicpolyatomic

Molecular CompoundsMolecular Compounds

Molecular compoundsMolecular compounds

made of just nonmetalsmade of just nonmetals

smallest piece is a moleculesmallest piece is a molecule

can’t be held together because of can’t be held together because of opposite chargesopposite charges

can’t use charges to figure out how can’t use charges to figure out how many of each atommany of each atom

EasierEasier

Ionic compounds use charges to determine how many Ionic compounds use charges to determine how many of eachof each

Have to figure out chargesHave to figure out charges

Have to figure out numbersHave to figure out numbers

Molecular compounds name tells you the number of Molecular compounds name tells you the number of atomsatoms

Uses prefixes to tell you the numberUses prefixes to tell you the number

PrefixesPrefixes

1 mono-1 mono-

2 di-2 di-

3 tri-3 tri-

4 tetra-4 tetra-

5 penta-5 penta-

6 hexa-6 hexa-

7 hepta-7 hepta-

8 octa- 8 octa-

PrefixesPrefixes

9 nona-9 nona-

10 deca-10 deca-

One exception is we don’t write mono- if One exception is we don’t write mono- if there is only one of the first element.there is only one of the first element.

Name TheseName These

NN22OO

NONO22

ClCl22OO77

CBrCBr44

COCO22

BaClBaCl22

Write formulas for theseWrite formulas for these

diphosphorus pentoxidediphosphorus pentoxide

tetraiodide nonoxidetetraiodide nonoxide

sulfur hexaflouridesulfur hexaflouride

nitrogen trioxidenitrogen trioxide

Carbon tetrahydrideCarbon tetrahydride

phosphorus trifluoridephosphorus trifluoride

aluminum chloridealuminum chloride

Naming AcidsNaming Acids

a little tricky so pay attentiona little tricky so pay attention

AcidsAcids

Compounds that give off hydrogen ions Compounds that give off hydrogen ions when dissolved in waterwhen dissolved in water

Must have H in them (Must have H in them (somewhere)somewhere)

will always be some H next to an anionwill always be some H next to an anion

The anion determines the name.The anion determines the name.

Naming acidsNaming acids

If the anion attached to hydrogen ends in If the anion attached to hydrogen ends in -ide-ide, put the , put the prefix prefix hydro- hydro- and change -and change -ideide to to -ic acid-ic acid

HCl - hydrogen ion and chlorHCl - hydrogen ion and chlorideide ion ion

hydrohydrochlorchloric acidic acid

HH22S hydrogen ion and sulfS hydrogen ion and sulfideide ion ion

hydrohydrosulfursulfuric acidic acid

Naming AcidsNaming Acids

If the anion has oxygen in itIf the anion has oxygen in it

it ends in -ate or -iteit ends in -ate or -ite

change the suffix change the suffix -ate -ate to to -ic acid-ic acid

HNOHNO33 Hydrogen and nitr Hydrogen and nitrateate ions ions

NitrNitric acidic acid

change the suffix change the suffix -ite -ite to to -ous acid-ous acid

HNOHNO22 Hydrogen and nitr Hydrogen and nitriteite ions ions

NitrNitrous acidous acid


HFHF

HH33PP

HH22SOSO44

HH22SOSO33

HCNHCN

HH22CrOCrO44


Hydrogen will always be firstHydrogen will always be first

name will tell you the anionname will tell you the anion

make the charges cancel out.make the charges cancel out.

Starts with hydro- no oxygen, -ideStarts with hydro- no oxygen, -ide

no hydro, no hydro, -ate -ate comes from comes from -ic-ic, , -ite -ite comes from comes from -ous-ous

Write formulas for theseWrite formulas for these

hydroiodic acidhydroiodic acid

acetic acidacetic acid

carbonic acidcarbonic acid

phosphorous acidphosphorous acid

hydrobromic acidhydrobromic acid

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Atoms, Ions and Molecules