gps sc1. students will analyze the nature of matter and its classifications. c. predict formulas for...
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GPS
SC1. Students will analyze the nature of matter and its classifications.
c. Predict formulas for stable ionic compounds (binary and tertiary) based on balance of charges.
d. Use IUPAC nomenclature for both chemical names and formulas of:
• Ionic compounds• Covalent compounds• Acidic compounds
Vocabulary
• Ion Oxidation number
• Cation Ionic compound
• Anion Covalent molecule
• Polyatomic ions Transition metals
• Binary compounds
• Monatomic ions
•Name both ions:•Name the cations 1st, •Anion 2nd
Change the ending of the anion to ~ide
EX: NaCl =
Sodium ChlorideRETURN TO BEGINNING
ROMAN NUMERALS???
•Transition metals can exist in more than one oxidation state (have more than 1 charge)
To determine the charge on the ion in question:1. Determine the charge of the ANION (look on periodic table)2. Look at the number of anions present (written down below)3. Determine the TOTAL negative charge4. Look at the number of cations present5. Divide TOTAL negative charge by number of cations present6. This is the Roman numeral you place in ( ) after the cation name
Show me an example
BACK TO NAME
To determine the charge on the ion in question:1. Determine the charge of the ANION (look on periodic table)2. Look at the number of anions present (written down below)3. Determine the TOTAL negative charge4. Look at the number of cations present5. Divide TOTAL negative charge by number of cations present6. This is the Roman numeral you place in ( ) after the cation name
Fe2O3
1. Oxygen’s charge is –2 2. There are 3 anions present 3. Total –charge is -64. There are 2 cations present5. 6/2= 3 6. Therefore each Fe caion must have a +3 charge
Iron (III)BACK TO NAME
•Name both ions•Use proper roman numeral in ( )with the cation•Change the ending of the anion to ~ide
EX: FeCl2 =
Iron (II) ChlorideRETURN TO BEGINNING
How do I figure out the
roman numeral?
•Name cation •If anion is: •single element change the ending of the anion to ~ide•also polyatomic write name of anion
EX: NH4Cl = Ammonium ChlorideEX: NH4NO3=Ammonium Nitrate
RETURN TO BEGINNING
•Name the cation•Name the anion
*will end with ~ate or ~ite* (hydroxide is exception)
EX: LiCO3 = Lithium Carbonate
RETURN TO BEGINNING
Practice
1. NH4Cl _____________________________
2. Ni2CO3 ____________________________
3. Cr(OH)3 ___________________________
4. CoSO4 ___________________________
5. NH4 NO3 __________________________
6. (NH4)2 CO3 ________________________
7. Au2 SO4 _________________________
Naming Ionic Compounds
• Common Anions:– Oxygen= oxide– Sulfur= sulfide– Phosphorus= phosphide– Nitrogen= nitride
Writing Ionic Compounds/ formulas
• To write formula: • Always write metal 1st; nonmetal 2nd • Write symbols w/charges• Drop charges• Cross superscripts to other
subscripts to write completed formula.
• Aluminum sulfide
• magnesium sulfide
• sodium sulfide
– Al3+ + S
– Mg2+ + S
– Na+ + S2
Al2S3
MgS
Na2S
C. Ionic Nomenclature
Ionic Cpmds w/ Polyatomic ions (PA)
• PA ions: ions made up of more than one atom. The charge assigned to a PA ion represents the charge on the entire group. Ex.) NH4
+1 = +1 charge on the entire ammonium ion
• To determine the name of cmpds w/ PA ions, follow the same rule as naming monatomic ionic compounds.
– cation= name of cation or polyatomic cation– anion= name of polyatomic anion ( do not change ending)– balance the charges of the cation and anion– Ex.) sodium & nitrate = Na+1 + NO3
-1 → NaNO3
• If there is >1 polyatomic ions in the compound, place a parenthesis around the entire ion and write the subscript outside the parenthesis.
• Ex.) Magnesium & nitrate= Mg+2 + NO3-1 → Mg(NO3)2
• Ex.) Aluminum & carbonate= Al+3 + CO3-2 → Al2(CO3)3
Ionic Cpmds w/ Polyatomic ionsName Formula
Ammonium Oxide
Sodium phosphate
Sodium nitrate
Magnesium sulfate
NH4OH
Ca(OH)2
KNO3
Li2CO3
Ionic Cpmds w/ Transition Metals
• Oxidation number: represents the charge on a monatomic ion, i.e. ionic charge.
• Some transition metals can form >1 oxidation state, so the charge of the different ion must be indicated.
• Ex) Iron has two charges: Fe 2+, Fe 3+
• Following the same rules for naming & writing formulas.• Except: Transition metal ionic compounds: use roman
numeral in parenthesis after metal name to indicate oxidation # of transition metal.
• Ex) Pb+2 + Cl-1 → PbCl2 = Lead (II) chloride • Ex) Cu2+ + Cl → CuCl2 = Copper (II) chloride
Common ions of Transition Metals & other Metals
Group Ions
4 Ti 2+ , Ti 3+
5 V 2+ , V 3+
6 Cr 2+ , Cr 3+
7 Mn 2+ , Mn 3+ , Tc 2+
8 Fe 2+ , Fe 3+
9 Co 2+ , Co 3+
10 Ni 2+, Pd 2+, Pt 2+, Pt 4+
11 Cu1+, Cu 2+, Ag1+, Au1+, Au3+
12 Zn 2+, Cd2+, Hg22+, Hg2+
13 Ga2+, Ga3+, In1+, In2+, In3+,
Tl 1+, Tl 3+
14 Sn 2+, Sn 4+, Pb 2+, Pb 4+
Ionic Cpmds w/ Transition MetalsName Formula
Copper (II) Oxide
Iron (II) Sulfide
Cobalt (III) Chloride
Titanium (II) nitride
TiO
FeCl3
Cu2O
CuO
• Then you have a binary molecular compound with 2 nonmetals.
• They share valence electrons instead of exchanging them to form ions…..
• Not cations or anions formed.
Molecular Compounds
• Binary Molecular Cmpd: AKA – Covalent molecules
• A binary compound is a cmpd formed by the combination of 2 elements btwn 2 nonmetals that share valence electrons.
Names for molecular binary compounds consist of two words.
• The 1st word is a prefix + a complete element’s name. (No prefix is used if there’s only 1 atom of the 1st element).
– Ex. CO2 ------------1st name= Carbon
• The 2nd word is a prefix plus the root of the element’s name plus the ending -ide.
• [PREFIX + ROOT NAME OF ELEMENT + -IDE]
– Ex. CO2 ------------2nd name= dioxide
– CO2 =Carbon dioxide
*Prefix: tells how many atoms of each element are present in the compound.
• Common Greek prefixes used in chemical
names
Prefix #
mono 1
Di (or –bi) 2
tri 3
tetra 4
penta 5
hexa 6
hept 7
octa 8
nona 9
deca 10
Writing formulas for covalent compounds:
• Write the symbols for each element
• If the atom has a prefix, then write the number representing the prefix as a subscript after the element’s symbol.
Practice
• Example:• Diphosphorous Trisulfide • write symbol: P S
• Write the subscript that represents the prefix: P2S3
• - Nitrogen Trichloride • write symbol: N Cl
• Write the subscript that represents the prefix: NCl3
Write the chemical formulas for the following compounds
• Dinitrogen Hexafluoride
• Carbon Dioxide
• Silicon Tetrafluoride
• Carbon Tetrabromide
Electron Configuration in Ionic Bonding
• Valence electrons are usually the only ones involved in bonding– Shown as electron dot structures (Lewis dot
structures)
• The number of valence electrons is related to the group number
• Formula Unit- lowest whole number ratio of ions in ionic compound; ionically bonded
• Ionic compound- compounds made of cations & anions; formed from xfer or exchange of v.e.o Usually a metal (cation) & nonmetal (anion)o Smallest unit= formula unito Solid at room temp.– High MP
• Ion-charged atom that has lost or gained valence electrons.
• Cation- group of atoms that lose e- to become + charged
• Anion- group of atoms that gain e- to become – charged
Ionic Binary Compounds • Monatomic ions- ions made of 1 atom• Group 1 lose 1 e- 1+
• Group 2 lose 2e- 2+
• Group 3 lose 3 e- 3+
• Group 14- bonds covalently (no ionic bond)• Group 15 gain 3 e- 3-
• Group 16 gain 2 e- 2-
• Group 17 gain 1 e- 1-
• Group 18 Noble gases- inert
Electron Configuration in Ionic Bonding
• Electron Configurations for Cations– The octet rule applies to most atoms in compounds– An atom’s loss of valence electrons produces a
cation (positively charged ion)• The most common cations are produced by the loss of
valence electrons from metal atoms
• Most metals atoms have one to three valence electrons, which are easily removed
Electron Configuration in Ionic Bonding
• Electron Configurations for Anions– The gain of negatively charged electrons by a
neutral atom produces anions– Ions that are produced when atoms of chlorine,
or other halogens, gain electrons are called halides
• All halides have a 1- charge
– For atoms from the oxygen group to gain a noble gas configuration, they must gain 2 valence electrons, resulting in a 2- ion
Ionic Bonds
• Formation of ionic compounds– Anions and cations have opposite charges, thus
they attract one another• The forces of attraction that bind these ions are called
ionic bonds• Compounds that consist of electrically neutral groups
of ions are called ionic compounds• The total positive charges must be balanced by the
total negative charges• Ex: Na+ and Cl- form NaCl• Ionic bonds can be explained with electron config.
Ionic Bonds
• Properties of ionic compounds– At room temperature, most are crystalline
solids• The component ions are arranged in repeating 3-
dimensional patterns called unit cells
• In this arrangement, each ion is attracted strongly to each of its neighbors and repulsions are minimized
• The large attractive forces result in a very stable structure
Electron Configuration in Ionic Bonding
• Transition metals have varying numbers of valence electrons– Fe can lose two or three electrons, resulting in a 2+ or 3+
charge– Some ions formed by transition metals do not attain a noble
gas configuration, so are exceptions to the octet rule• Ag would have to lose 11e-, or gain 5e- to have a noble gas
configuration• Instead, atoms with more than 3 valence electrons tend to end up
with 18 e- in their outer energy level– Called a pseudo noble gas configuration– Having 18 valence e- is relatively favorable in compounds– Transition elements to the far right tend to do this– Cu, Au, Cd, and Hg have pseudo noble gas configurations
Bonding in Metals
• Metallic bonds and metallic properties– Metals are made up of closely packed ions,
surrounded by mobile valence electrons • These valence electrons can move freely from one
part of the metal to another
• Metallic bonds consist of the attraction of the freely-floating valence electrons to the positively charged metal ions
– Explains many of the properties of metals
Bonding in Metals
• Properties of metals– Good conductors of electricity because electrons
can flow freely in them– Ductile and malleable because of the mobility of
the valence electrons
• Crystalline structure of metals– Metals that contain just one type of atom are
among the simplest of all crystalline solids• Metal atoms are arranged in very compact and orderly
patterns
Bonding in Metals• Alloys
– Most metals you encounter are alloys– Alloys are mixtures composed of two or more
elements, at least one of which is a metal• Prepared by melting the ingredients, then allowing them
to cool• There are many different kinds of alloys
– Ex: Brass is an alloy of copper and zinc
• Alloys are important because their properties are often superior to those of the individual elements
– Today, the most important alloys are steels
• Two types of alloys are substitutional alloys and interstitial alloys (depends on formation)
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