6.3 naming compounds and writing formulas chapter 6 chemical bonds

6.3 Naming Compounds 6.3 Naming Compounds and Writing Formulas and Writing Formulas

Chapter 6 Chapter 6

Chemical BondsChemical Bonds

What are we going to What are we going to learn?learn?

• How to write the name and formula How to write the name and formula of ionic and covalently bonded of ionic and covalently bonded compoundscompounds

Naming Ionic Naming Ionic CompoundsCompounds

• Ionic compound Ionic compound namename: distinguishes : distinguishes the the compoundcompound from from otherother ionic ionic compounds containing the compounds containing the same same elementselements

• Name =Name = wordswords (ex: calcium (ex: calcium chloride)chloride)

• Ionic compound Ionic compound formulaformula: describes : describes the the ratioratio of the of the ionsions in the in the compoundcompound

• Formula = Formula = numbers of elementsnumbers of elements (ex: CaCl(ex: CaCl22))

Binary CompoundsBinary Compounds

• If a If a compoundcompound is made from only is made from only twotwo elements elements is a is a binarybinary compound compound

(Ex: salt is a binary compound made (Ex: salt is a binary compound made of sodium and chlorine - sodium of sodium and chlorine - sodium chloride)chloride)

What’s in a Name?What’s in a Name?

• To To namename a binary compound: list the a binary compound: list the name of the name of the cationcation ( (++ ion) ion) followed followed byby the name of the the name of the anionanion ( (- - ion) ion)

Cations – First in NamingCations – First in Naming

• CationCation: simply the name of the : simply the name of the metalmetal (no changes) (no changes)

• Ex: sodium atom and sodium ionEx: sodium atom and sodium ion

• This This works forworks for groups groups 1A1A, , 2A2A and and AluminumAluminum

• Group Group 1A1A has a has a 11++ charge charge• Group Group 2A2A has a has a 22++ charge charge• Aluminum (Group Aluminum (Group 3A3A) has a ) has a 33++

chargecharge

• Transition metalsTransition metals with with more than more than oneone possible possible chargecharge have a different have a different naming strategynaming strategy

• NameName of the ion contains a of the ion contains a RomanRoman numeralnumeral to indicate the to indicate the chargecharge

• Ex: copper (II) ionEx: copper (II) ion

Anions – The FollowersAnions – The Followers

• AnionAnion: use name of the : use name of the nonmetalnonmetal with the with the suffix suffix ––ideide replacingreplacing –ine –ine

(ex: chlorine atom and chloride ion(ex: chlorine atom and chloride ion))• NonmetalsNonmetals are on the are on the right sideright side of of

the periodic the periodic tabletable• Ex: sodium chlorideEx: sodium chloride

(cation) (anion)(cation) (anion)

FormulasFormulas• If you know the If you know the namename of an ionic of an ionic

compound, you can compound, you can writewrite its its chemical formula chemical formula

• Chemical formula includes Chemical formula includes chemical chemical symbolssymbols of the elements and of the elements and numbersnumbers (indicating (indicating amounts of amounts of each element)each element)

How do you write a How do you write a formula?formula?

• Write the symbol of the Write the symbol of the cationcation first first • Follow with the symbol of the Follow with the symbol of the anionanion • Use Use subscriptssubscripts to show the to show the ratioratio of of

the ions in the compoundthe ions in the compound

Polyatomic IonsPolyatomic Ions• A A covalently bonded group of atomscovalently bonded group of atoms

that has a that has a positive or negativepositive or negative charge charge and and acts as a unitacts as a unit

• Ex: nitrate (NO)Ex: nitrate (NO)3-3-, sulfate (SO, sulfate (SO44))2-2-, , phosphate (POphosphate (PO44))3-3-

Molecular CompoundsMolecular Compounds

• NameName and and formulaformula of a molecular of a molecular compound describe the compound describe the typetype and and number of atomsnumber of atoms in a in a moleculemolecule of of the compoundthe compound

• These These elementselements are usually on the are usually on the right sideright side of the periodic table of the periodic table

• ElementsElements in the compound in the compound share share electronselectrons

The molecules in the top row bond by sharing electrons. The compounds in the bottom row join in polar covalent bonds.

Naming a Molecular Naming a Molecular CompoundCompound

• Most metallicMost metallic element name appears element name appears firstfirst (most (most left left in the periodic table)in the periodic table)

• Name of the Name of the second elementsecond element is is changed to end in the suffix changed to end in the suffix --ideide

• Ex: carbon dioxide Ex: carbon dioxide

• PrefixesPrefixes indicate indicate amountamount of atoms in of atoms in the the moleculemolecule

• Ex: Ex: di di shows that there are shows that there are twotwo carbon carbon atomsatoms in the molecule in the molecule

Molecular FormulaMolecular Formula

• WriteWrite the the symbolssymbols for the elements for the elements in the in the orderorder the elements the elements appearappear in in the the namename

• PrefixesPrefixes in the compound name in the compound name indicateindicate the the number of atomsnumber of atoms of of each elementeach element in the molecule in the molecule

• PrefixesPrefixes appear as appear as subscriptssubscripts in the in the formulaformula

Writing Chemical Formulas Writing Chemical Formulas for Binary for Binary

Compounds PracticeCompounds Practice• 1 - Write the symbols for the elements.1 - Write the symbols for the elements.

2 - Look up element ion charges and write 2 - Look up element ion charges and write them as superscripts to the right of the them as superscripts to the right of the elemental symbols.elemental symbols.3 - Use the correct combination of ions to 3 - Use the correct combination of ions to produce a compound with a net charge of produce a compound with a net charge of zero. Multiple ions are indicated with zero. Multiple ions are indicated with subscripts. subscripts.

• lithium oxide lithium oxide • potassium chloride potassium chloride • calcium oxidecalcium oxide• barium bromide barium bromide

Writing Chemical Formulas Writing Chemical Formulas for Binary for Binary

Compounds PracticeCompounds Practice• 1 - Write the symbols for the elements.1 - Write the symbols for the elements.

2 - Look up element ion charges and write 2 - Look up element ion charges and write them as superscripts to the right of the them as superscripts to the right of the elemental symbols.elemental symbols.3 - Use the correct combination of ions to 3 - Use the correct combination of ions to produce a compound with a net charge of produce a compound with a net charge of zero. Multiple ions are indicated with zero. Multiple ions are indicated with subscripts. subscripts.

• lithium oxide lithium oxide LiLi22OO• potassium chloride potassium chloride KClKCl• calcium oxide calcium oxide CaOCaO• barium bromide barium bromide BaBrBaBr22

Writing Chemical Formulas for Writing Chemical Formulas for Binary Compounds with Binary Compounds with

Polyatomic Ions Polyatomic Ions • lithium carbonate lithium carbonate • calcium nitratecalcium nitrate• ammonium sulfideammonium sulfide• sodium sulfatesodium sulfate

Writing Chemical Formulas for Writing Chemical Formulas for Binary Compounds with Binary Compounds with

Polyatomic Ions Polyatomic Ions • lithium carbonate lithium carbonate LiLi22COCO33

• calcium nitrate calcium nitrate Ca(NOCa(NO33) ) 22

• ammonium sulfide ammonium sulfide (NH4) (NH4) 22SS

• sodium sulfate sodium sulfate NaNa22SO4SO4

Writing Chemical Formulas Writing Chemical Formulas for Transition Metals for Transition Metals

PracticePractice• Lead (IV) carbonate Lead (IV) carbonate • Copper (II) nitrate Copper (II) nitrate • Iron (III) oxideIron (III) oxide• Tin (IV) fluoride Tin (IV) fluoride

Writing Chemical Formulas Writing Chemical Formulas for Transition Metals for Transition Metals

PracticePractice• Lead (IV) carbonate Lead (IV) carbonate Pb(COPb(CO33))22

• Copper (II) nitrate Copper (II) nitrate Cu(NOCu(NO33))22

• Iron (III) oxide Iron (III) oxide Fe Fe22OO33

• Tin (IV) fluoride Tin (IV) fluoride SnFSnF44

Writing Chemical Names Writing Chemical Names for Transition Metals for Transition Metals

PracticePractice• Fe(NOFe(NO33))2 2

• CuFCuF2 2

• NiS NiS

• FeClFeCl22

Writing Chemical Names Writing Chemical Names for Transition Metals for Transition Metals

PracticePractice• Fe(NOFe(NO33))2 2 iron (II) nitrateiron (II) nitrate

• CuFCuF2 2 copper (II) fluoridecopper (II) fluoride

• NiS NiS nickel (II) sulfidenickel (II) sulfide

• FeClFeCl22 iron (II) chlorideiron (II) chloride

Writing Chemical Formulas Writing Chemical Formulas PracticePractice

• zinc carbonate zinc carbonate • barium oxide barium oxide • cadmium fluoride cadmium fluoride • magnesium sulfide magnesium sulfide • lithium phosphate lithium phosphate

Writing Chemical Formulas Writing Chemical Formulas PracticePractice

• zinc carbonate zinc carbonate ZnCOZnCO33

• barium oxide barium oxide BaOBaO

• cadmium fluoridecadmium fluorideCdFCdF2 2

• magnesium sulfidemagnesium sulfide MgSMgS

• lithium phosphate lithium phosphate LiLi33POPO44

Writing Chemical Names Writing Chemical Names PracticePractice

• FeFFeF22

• FeFFeF3 3

• HgHg22BrBr22

• HgBrHgBr22

Writing Chemical Names Writing Chemical Names PracticePractice

• FeFFeF22 iron (II) fluorideiron (II) fluoride

• FeFFeF3 3 iron (III)fluorideiron (III)fluoride

• HgHg22BrBr22 mercury (I) bromidemercury (I) bromide

• HgBrHgBr22 mercury (II) bromidemercury (II) bromide

Writing Chemical Names Writing Chemical Names PracticePractice

• BaSOBaSO44

• FeFFeF22

• CuCOCuCO33

• CaSCaS• MgOMgO• KClKCl

Writing Chemical Names Writing Chemical Names PracticePractice

• BaSOBaSO44 barium sulfatebarium sulfate

• FeFFeF22 iron (II) fluorideiron (II) fluoride

• CuCOCuCO33 copper (II) carbonatecopper (II) carbonate

• CaSCaS calcium sulfidecalcium sulfide• MgOMgO magnesium oxidemagnesium oxide• KClKCl potassium chloridepotassium chloride

• NO NO

• NN22O O

• NONO22

• NN22OO55

• NN22OO33

• NO NO nitrogen monoxidenitrogen monoxide

• NN22O O dinitrogen monoxidedinitrogen monoxide

• NONO22 nitrogen dioxidenitrogen dioxide

• NN22OO55 dinitrogen pentoxidedinitrogen pentoxide

• NN22OO33 dinitrogen trioxidedinitrogen trioxide