The Octet Rule Atoms tend to gain, lose, or share electrons until they have eight valence electrons. 8 OCTET RULE Rule in which all elements want to satisfy.

The Octet Rule Atoms tend to gain, lose, or share electrons until they have eight valence electrons. 8 OCTET RULE Rule in which all elements want to satisfy. All elements want to have a full or empty outermost shell/energy level. They want to have 8 valence electrons to become stable. Valence Electrons - Outermost electrons on the outermost shell/energy level Valence electrons are the available electrons for bonding. The Group number tells you the number of valence electrons.

Atomic Structure ATOMS ISOTOPES IONS Differ by number of protons
Differ by number of neutrons IONS Differ by number of electrons

Formation of Cation sodium atom Na sodium ion Na+ 11p+ 11p+ e- e- e-
loss of one valence electron 11p+ e- e- e- e- e- e-

Formation of Anion chlorine atom chloride ion Cl1- Cl 17p+ 17p+ e-
gain of one valence electron e- e- e- e- e- e- e- e- 17p+ e- e- e- e- e- e- e- e- e- e-

Formation of Ionic Bond
chloride ion Cl1- sodium ion Na+ 11p+ e- 17p+ e-

Various Ions Zn2+ Ag1+ Many elements have a tendency to gain or lose enough electrons to attain the same number of electrons as the noble gas closest to them in the periodic table. Monatomic ions contain only a single atom. Charges of most monatomic ions derived from the main group elements are predicted by simply looking at the periodic table and counting how many columns an element lies from the extreme left or right. Zumdahl, Zumdahl, DeCoste, World of Chemistry 2002, page 74

Periodic Table with Group Names

Predicting Ionic Charges
Group 1: Alkali Metals, 1 valence electron Lose 1 electron to form +1 ions H+1 Li+1 Na+1 K+1

Group 2: Alkaline Earth Metals, 2 valence e- Loses 2 electrons to form +2 ions Be+2 Mg+2 Ca+2 Sr+2 Ba+2

Groups : Transition Metals Many transition elements have more than one possible oxidation state. Iron(III) = Fe+3 Iron(II) = Fe+2

Group 13: Boron Group, 3 valence e- Loses 3 electrons to form +3 ions B+3 Al+3 Ga+3

Group 14: Carbon Group, 4 valence e- Loses 4 electrons or gains 4 electrons (±4) C-4 Si+4 Pb+4

Group 15: Nitrogen Group, 5 valence e- N-3 Nitride Gains 3 electrons to form -3 ions P-3 Phosphide As-3 Arsenide

Group 16: Oxygen Group, 6 valence e- O-2 Oxide Gains 2 electrons to form -2 ions S-2 Sulfide Se-2 Selenide

Group 17: Halogens, 7 valence e- Gains 1 electron to form -1 ions F-1 Fluoride Br-1 Bromide Cl-1 Chloride I-1 Iodide

Group 18: Noble Gases, 8 valence e-, Except He which has 2 valence e STABLE INERT- Nonreactive, do not form ions! Full outermost energy level. Maximum number of valence electrons possible.

Naming Binary Compounds
Naming Compounds MgSO4 K2O NaCl CaS NH4OH

Metal vs. Non-metal Naming
Binary Metal vs. Non-metal Ionic Compound First - write the name of the metal (Cation) Name does not change Then - write the name of the nonmetal (Anion) with an -ide ending. Metal vs. Non-metal Naming Examples: NaCl - sodium chloride CaI2 - calcium iodide Li2O - lithium oxide Ag3N – silver nitride Try These: MgS - ZnBr2 - Al2O3 - Fe2O3- Magnesium sulfide Zinc bromide Aluminum oxide Iron(III) oxide (rust)

Naming Polyatomic Compounds
Nomenclature involving Polyatomic Ions The prefix Poly- means “many” or “more than 1” Polyatomic ion – an ion that has more than one type of element, covalently bonded to each other yet it still contains a (+) or (-) charge. Naming Polyatomic Compounds First - write the name of the metal. (Cation) Then - write the name of the polyatomic ion WITHOUT changing its name. The only "positive" polyatomic ion used in this class is ammonium, NH4+. Examples: MgSO4 - magnesium sulfate CaCO3 - calcium carbonate NaOH - sodium hydroxide NH4NO3 - ammonium nitrate Try These: KOH – Li3PO4 – AgNO3 – Al2(SO4)3 – Potassium hydroxide Lithium phosphate Silver nitrate Aluminum sulfate

Roman Numerals Names Containing Roman Numerals in (Parentheses)
If the positive element has more than one possible oxidation number, or if it is out of character, its oxidation is shown as a Roman numeral in parentheses after its name. Roman Numerals Try These: HgI2 – FeO – MnO – SnCl2 – CrBr3 – Examples: Fe2O3 - Iron (III) oxide Fe2(SO4)3 – iron (III) sulfate CuCl - copper (I) chloride Pb (CO3)2 – lead (IV) carbonate mercury(II) iodide iron(II) oxide manganese (II) oxide tin(II) chloride chromium(III) bromide

Concept Review Naming Compounds
Concept Understanding: Write the correct name for each of these compounds: Fe(OH)2 (NH4)3PO4 AlPO4 Cu(C2H3O2)2 CaCO3 NH4OH Cr2(SO4)3 Mg(NO3)2 Concept Review Naming Compounds Iron(II) hydroxide Ammonium phosphate Aluminum phosphate Copper(II) acetate Calcium carbonate Ammonium Hydroxide Chromium(III) sulfate Magnesium nitrate

“Perhaps one of you gentlemen would mind telling me just
what is outside the window that you find so attractive..?” Image courtesy NearingZero.net

Writing Chemical Formulas
A simple way to learn to write chemical formulas: Write the oxidation number above each element. Cross the oxidation numbers and write the oxidation number (without plus or minus) of one element as the subscript of the other element. Reduce the subscripts (number of atoms) to their simplest form, if needed. Writing Chemical Formulas WHAT IS THE CHEMICAL FORMULA FOR CALCIUM CHLORIDE?

Writing Formulas Continued…
A simple way to learn to write chemical formulas continued... Write the oxidation number above each element. Cross these and write the oxidation number (without plus or minus charge) of one element as the subscript of the other element. +1 -2 = Li2O Lithium oxide Li O +2 -3 = Ba3N2 Barium Nitride Ba N Writing Formulas Continued… +2 -2 = MgS Magnesium Sulfide Mg S +1 -1 = KCl Potassium Chloride K Cl +1 -1 = NaI Sodium Iodide Na I

Writing Formulas with polyatomic ions
A simple way to learn to write chemical formulas with polyatomic ions Write the oxidation number above each (putting parantheses around the polyatomic ion). Cross these and write the oxidation number (without plus or minus charge) of each ion as the subscript of the other atom/polyatomic ion. +1 -1 = NaOH Sodium hydroxide Na (OH) +2 -2 Writing Formulas with polyatomic ions = CaCO3 Calcium carbonate Ca (CO3) +2 -3 Zinc phosphate = Zn3(PO4)2 Zn (PO4) +3 -1 = Al(NO3)3 Aluminum nitrate Al (NO3) +1 -2 = (NH4)2SO3 Ammonium sulfite (NH4) (SO3)

Practice Naming Ionic Compounds
1. NaCl = Sodium Chloride 2. K2O = Potassium Oxide 3. CaF2 = Calcium Fluoride 4. Fe2O3= Iron (III) Oxide 5. CuCl = Copper (I) Chloride 6. NaOH = Sodium Hydroxide 7. AlPO4 = Aluminum Phosphate 8. Mg(NO3)2 = Magnesium Nitrate

Example: Aluminum Chloride
Criss-Cross Rule Example: Aluminum Chloride Aluminum Chloride Step 1: write out name with space Al Cl 3+ 1- Step 2: write symbols & charge of elements Al Cl Step 3: 1 3 criss-cross charges as subsrcipts Step 4: AlCl 3 combine as formula unit (“1” is never shown)

Example: Aluminum Chloride
Criss-Cross Rule Example: Aluminum Chloride Step 1: Aluminum Chloride Step 2: Al3+ Cl1- Step 3: Al Cl 1 3 Step 4: AlCl 3

Example: Aluminum Oxide
Criss-Cross Rule Example: Aluminum Oxide Step 1: Aluminum Oxide Step 2: Al3+ O2- Step 3: Al O 2 3 Step 4: Al2O3

Example: Magnesium Oxide
Criss-Cross Rule Example: Magnesium Oxide Step 1: Magnesium Oxide Step 2: Mg2+ O2- Step 3: Mg O 2 2 Step 4: Mg2O2 Step 5: MgO

Naming Ionic Compounds
Ionic Compounds: Formed from oppositely charged ions Cations: Positively charged ions (METALS) give e- away Anions: Negatively charged ions (NONMETALS) take e- in Positive ions (Cations) take the names of the metal from which they are derived: Na+ = Sodium ion, Ca+2 = Calcium ion, Al+3 = Aluminum ion (The name DOES NOT CHANGE) Negative ions (Anions) are named by adding the suffix -ide to the stem of the name of the nonmetal from which they are derived: Cl- = Chloride ion, O-2 = Oxide ion, N-3 = Nitride ion (-ide is added to the end)

CaCl2 = calcium chloride
Naming Ionic Compounds 1. Cation (Metal) first, then Anion (Nonmetal) 2. Monatomic Cation = name of the element Ca+2 = calcium ion Na+ = sodium ion Al+3 = aluminum ion 3. Monatomic Anion = root name + -ide Cl- = chloride O-2 = oxide CaCl2 = calcium chloride Na2O = sodium oxide

Naming Ionic Compounds continued
When a metal forms more than one ion (as the transition metals do), it is necessary to distinguish between these ions. The accepted practice today is to indicate the charge of the ion by a ROMAN NUMERAL in (parentheses) immediately following the name of the metal. The following are the only metals with multiple ions you need to know: Fe+2 = Iron (II) Fe+3 = Iron (III) Hg+ = Mercury (I) Hg+2 = Mercury (II) Cu+ = Copper (I) Cu+2 = Copper (II) Mn+2 = Manganese (II) Mn+3 = Manganese (III) Pb+2 = Lead (II) Pb+4 = Lead (IV) Cr+2 = Chromium (II) Cr+3 = Chromium (III)

Naming Ionic Compounds continued
Polyatomic Ions – An ion consisting of a group of bonded atoms. Polyatomic ions have a suffix ending in –ate or –ite (except for OH- = hydroxide ion, NH4+ = Ammonium) The difference in the polyatomic ending, is in the number of Oxygen atoms. Polyatomic ions with more Oxygen atoms will take on the –ate suffix. Sulfate = (SO4-2) Nitrate (NO3-) Polyatomic ions with less Oxygen atoms will take on the –ite suffix. Sulfite = (SO3-2) Nitrite = (NO2-)

The Octet Rule Atoms tend to gain, lose, or share electrons until they have eight valence electrons. 8 OCTET RULE Rule in which all elements want to satisfy.

Similar presentations

Presentation on theme: "The Octet Rule Atoms tend to gain, lose, or share electrons until they have eight valence electrons. 8 OCTET RULE Rule in which all elements want to satisfy."— Presentation transcript:

Similar presentations

About project

Feedback

Log in

Auth with social network:

The Octet Rule Atoms tend to gain, lose, or share electrons until they have eight valence electrons. 8 OCTET RULE Rule in which all elements want to satisfy.

Similar presentations

Presentation on theme: "The Octet Rule Atoms tend to gain, lose, or share electrons until they have eight valence electrons. 8 OCTET RULE Rule in which all elements want to satisfy."— Presentation transcript:

Similar presentations

About project

Feedback