chemical nomenclature how to write and say chemical formulas general chemistry 10-11
TRANSCRIPT
Chemical NomenclatureChemical Nomenclature
How to write and say chemical How to write and say chemical formulasformulas
General Chemistry 10-11General Chemistry 10-11
ElementsElements
Elements are said with Elements are said with just their namejust their name Mg = magnesiumMg = magnesium Ca = calciumCa = calcium
Some elements never Some elements never exist by themselvesexist by themselves
These are called diatomic These are called diatomic moleculesmolecules There are seven of them There are seven of them
and they make a seven on and they make a seven on the periodic tablethe periodic table
The Diatomic MoleculesThe Diatomic Molecules These would still be said These would still be said
by their elemental name by their elemental name but would be written with but would be written with a subscript of 2a subscript of 2
NN22
OO22
FF22
ClCl22 BrBr22
II22
HH22
CompoundsCompounds
Most elements are not found separately Most elements are not found separately but combined in a compound with but combined in a compound with something elsesomething else
The reason for this is the octet ruleThe reason for this is the octet rule
We want 8…eight is great!
Octet RuleOctet Rule
Noble gases are what Noble gases are what all elements aspire to all elements aspire to be like electronicallybe like electronically
These elements have These elements have 8 electrons in highest 8 electrons in highest energy levelenergy level
Ionic BondIonic Bond
Atoms will either give up or take electrons Atoms will either give up or take electrons to get to have eight in their highest energy to get to have eight in their highest energy levellevel
ChargesChargesSodium now has a +1 charge since it has Sodium now has a +1 charge since it has
lost an electronlost an electronChlorine a minus charge since it gained an Chlorine a minus charge since it gained an
electronelectron
Ionic BondIonic BondOpposites attract, so a bond is formed Opposites attract, so a bond is formed
between the two of them.between the two of them.
(or until water breaks us apart)
Ionic CompoundIonic Compound
The combination of NaThe combination of Na++ and Cl and Cl-- form the form the compound NaClcompound NaCl
An ionic compound will always consist of:An ionic compound will always consist of:A metal ion (also called a cation, the + one)A metal ion (also called a cation, the + one)A non-metal ion (also called an anion, the - one)A non-metal ion (also called an anion, the - one)
CATION ALWAYS COMES BEFORE THE CATION ALWAYS COMES BEFORE THE ANION; both in the name and the formulaANION; both in the name and the formula
Naming Ionic CompoundsNaming Ionic Compounds
When naming ionic When naming ionic compoundscompounds
Just say the name of Just say the name of the metalthe metal
For the non-metal, For the non-metal, drop the ending and drop the ending and add -ide to it.add -ide to it.
NaCl = sodium NaCl = sodium chloridechloride
Practice Problem #1Practice Problem #1
Name the following Name the following ionic compoundsionic compounds
1.1. ZnOZnO
2.2. LiBrLiBr
3.3. MgMg33NN22
4.4. BaSBaS
5.5. KK33PP
Zinc oxideZinc oxide
Lithium bromideLithium bromide
Magnesium nitrideMagnesium nitride
Barium sulfideBarium sulfide
Potassium phosphidePotassium phosphide
Determining metal and non-metal Determining metal and non-metal chargecharge
Where are the metals on the periodic Where are the metals on the periodic table?table?Metals always have what charge?Metals always have what charge?
Where are the nonmetals?Where are the nonmetals?Nonmetals always have what charge?Nonmetals always have what charge?
We’ll see the charges of the different families on
the following slide.
Using the periodic Table to find an Using the periodic Table to find an ion’s chargeion’s charge
We’re going to forget all about the middle of the table for now.
+1
+2
-1
-2
-3
-4
Combining metals and nonmetalsCombining metals and nonmetals
When combining a metal and a non-metal, the When combining a metal and a non-metal, the overall charge of the compound must be zero. overall charge of the compound must be zero.
You must balance out the overall
charge!
Combining metals and nonmetalsCombining metals and nonmetals
Take for instance calcium nitride.Take for instance calcium nitride.What is the charge of the calcium ion?What is the charge of the calcium ion?What is the charge of the nitride ion?What is the charge of the nitride ion?
Combining metals and nonmetalsCombining metals and nonmetals
CaCa+2+2 means each calcium ion has 2 more means each calcium ion has 2 more electrons than it wantselectrons than it wants
NN-3-3 means each nitride ion needs 3 more means each nitride ion needs 3 more electrons.electrons.
The ions found they were still attracted to one another due to their opposing charges. And they all
lived happily ever after.
Practice Problem #2Practice Problem #2
Give the formulas for the following Give the formulas for the following compoundscompounds
1.1. Beryllium iodideBeryllium iodide
2.2. Potassium sulfidePotassium sulfide
3.3. Magnesium oxideMagnesium oxide
4.4. Strontium fluorideStrontium fluoride
BeIBeI22
KK22SS
MgOMgO
SrFSrF22
Now is the time to learn “SWITCHY SWITCHY”
and reduce!
Transition MetalsTransition Metals
The middle block of The middle block of elementselements
All cationsAll cations Most can take on Most can take on
multiple chargesmultiple charges Some ExceptionsSome Exceptions
Zn = +2Zn = +2Ag = +1Ag = +1
Transition metal compoundsTransition metal compounds
In order to tell what charge a transition In order to tell what charge a transition metal has, put its charge in parenthesismetal has, put its charge in parenthesis
For instance Copper (II) Oxide means… For instance Copper (II) Oxide means… the copper ion here has a +2 chargethe copper ion here has a +2 charge
For instance Copper (I) Oxide means… For instance Copper (I) Oxide means… the copper ion here has a +1 chargethe copper ion here has a +1 charge
What are the formulas of What are the formulas of these two ionic these two ionic compounds?compounds?
Practice Problem #3Practice Problem #3
Give the formula of the following Give the formula of the following compounds:compounds:
1.1. Tungsten (IV) ChlorideTungsten (IV) Chloride
2.2. Gold (III) phosphideGold (III) phosphide
3.3. Tin (II) fluorideTin (II) fluoride
4.4. Zinc sulfideZinc sulfide
WClWCl44
AuPAuP
SnFSnF22
ZnSZnS
Polyatomic IonsPolyatomic Ions
Sometimes, atoms get together but Sometimes, atoms get together but can’t quite get to an overall zero can’t quite get to an overall zero charge.charge.
This is where they become a This is where they become a polyatomic ionpolyatomic ion
They’re still a charged particle They’re still a charged particle (mostly anions) so they can combine (mostly anions) so they can combine with an opposing charged ion to with an opposing charged ion to produce a compoundproduce a compound
Naming is easy, we just say the Naming is easy, we just say the name of the polyatomic ionname of the polyatomic ion
With polyatomic ions we don’t have to
change the ending
Practice Problem #4Practice Problem #4
Name the following compoundsName the following compounds1.1. (NH(NH44))22SS
2.2. CaSOCaSO44
3.3. Ba(NOBa(NO33))22
4.4. KK22COCO33
5.5. MgMg33(PO(PO44))22
Ammonium sulfideAmmonium sulfide
Calcium sulfateCalcium sulfate
Barium nitrateBarium nitrate
Potassium carbonatePotassium carbonate
Magnesium phosphateMagnesium phosphate
Practice Problem #5Practice Problem #5
Write formulas for the following Write formulas for the following compounds compounds Aluminum nitrateAluminum nitrateBeryllium sulfateBeryllium sulfateCalcium phosphiteCalcium phosphiteAmmonium sulfiteAmmonium sulfiteStrontium nitriteStrontium nitrite
Al(NOAl(NO33))33
BeSOBeSO44
CaCa33(PO(PO33))22
(NH(NH44))22SOSO33
Sr(NOSr(NO22))22
Covalent BondsCovalent Bonds
Compounds formed by two non-metalsCompounds formed by two non-metalsMore of a sharing of electrons rather than More of a sharing of electrons rather than
a give-take relationshipa give-take relationship
Naming Covalent BondsNaming Covalent Bonds
Prefixes on back of periodic tablePrefixes on back of periodic table If there is only one of the first element, no If there is only one of the first element, no
prefix. Otherwise attach prefixprefix. Otherwise attach prefixSecond always gets prefix and -ide ending Second always gets prefix and -ide ending
(just like ionic anion)(just like ionic anion)Name theseName these
IClICl55NN22OO
Practice Problem #7Practice Problem #7
Name the following covalent compoundsName the following covalent compounds1.1. COCO22
2.2. PClPCl553.3. COCO
4.4. PP33FF66
Carbon dioxideCarbon dioxide
Phosphorous pentachloridePhosphorous pentachloride
Carbon monoxideCarbon monoxide
Triphosphorous hexaflourideTriphosphorous hexaflouride
Practice Problem #8Practice Problem #8
Give the formula for the following Give the formula for the following compoundscompounds
Sodium acetateSodium acetate Nickel (II) chlorideNickel (II) chloride Carbon dioxideCarbon dioxide Sulfur trioxideSulfur trioxide Triphosphorous tetrachlorideTriphosphorous tetrachloride
NaCNaC22HH33OO22
NiClNiCl22
COCO22
SOSO33
PP33ClCl44
One more thing…One more thing…
If the ionic compound begins with a hydrogen If the ionic compound begins with a hydrogen ion, it’s an acidion, it’s an acid
We name binary acids by adding hydro as a We name binary acids by adding hydro as a prefix to the root of the anion and add ic, then prefix to the root of the anion and add ic, then add the word acidadd the word acid
Name these:Name these: HClHCl HIHI HFHF HBrHBr
Acids involving polyatomic anionsAcids involving polyatomic anions
These are even easier,These are even easier,They’ll always involve oxygenThey’ll always involve oxygen If an -ate ion, use root of If an -ate ion, use root of
polyatomic and add -icpolyatomic and add -ic If an -ite ion, use root of If an -ite ion, use root of
polyatomic and add -ouspolyatomic and add -ousThen just add the word acidThen just add the word acid
If I ATE it I would say IC!
Practice Problem #6Practice Problem #6
Write the formulas for these acidsWrite the formulas for these acids1.1. Sulfuric acidSulfuric acid
2.2. Sulfurous acidSulfurous acid
3.3. Carbonic acidCarbonic acid
4.4. Nitric acidNitric acid
5.5. Nitrous acidNitrous acid
6.6. Phosphoric acidPhosphoric acid
7.7. Phosphorous acidPhosphorous acid
HH22SOSO44
HH22SOSO33
HH22COCO33
HNOHNO33
HNOHNO22
HH33POPO44
HH33POPO33