Chemical Nomenclature 1 Binary Ionic Compounds Type I
Chemical Nomenclature 1. Binary Ionic Compounds - Type I 2. Binary Ionic Compounds - Type II 3. Ionic Compounds & Polyatomic (Complex) Ions 4. Hydrated Ionic Compounds 5. Binary Covalent Compounds 6. Binary Acids 7. Oxy-Acids
Definitions n n n An IONIC COMPOUND consists of a metal cation bonded to a nonmetal anion. Electrostatic attraction holds them together. A COVALENT COMPOUND consists of two nonmetal atoms sharing valence electrons. A BINARY compound is one that is made of just two elements.
Type I Binary Ionic Compounds n The metal cations in these compounds have only ONE possible charge. Na+ sodium Zn 2+ zinc Al 3+ aluminum Ca 2+ calcium The charges are memorized or predicted using a periodic table! n The cations are bonded to nonmetal anions: O 2 oxide N 3 nitride Ffluoride Br bromide Notice that simple anions are always named with the suffix “ide”
n n In an ionic compound, the charges of the cations and anions must always cancel out. Subscripts are used if more than one atom is needed to cancel the charges: sodium chloride: Na+ and Cl- ® lithium oxide: Li+ and O 2 - ® aluminum bromide: Al 3+ and Br - ® Al. Br 3 Na. Cl Li 2 O
Examples: Type I Binary Ionic Compounds Write the formulas: Write the names: • Di-potassium oxide • K 3 N • zinc chloride • Ag. I • silver sulfide • Zn. Br 2 •
Type II Binary Ionic Compounds n These are ionic compounds where the metal cation can form TWO different charges. Fe 2+ iron (II) Fe 3+ iron (III) Ni 2+ nickel (II) Ni 3+ nickel (III) Co 2+ cobalt (II) Co 3+ cobalt (III) Cu+ copper (I) Cu 2+ copper (II)
Examples: Type II Binary Ionic Compounds Write the formulas: Write the names: • iron (II) oxide • Fe 2 O 3 • copper (II) chloride • Pb 3 P 2 • tin (IV) sulfide • Cu. Br • cobalt (III) selenide • Fe. Cl 3
Polyatomic (Complex) Ions n n n All of the cations and anions so far have been simple ions - single atoms that have lost or gained electrons. A molecule is a particle that forms when two or more atoms bond together. A complex ion is a charged molecule. Complex ions may be cations or anions. examples: nitrate: NO 3 - sulfate: SO 42 - hydroxide: OH-
Writing formulas with Complex Ions a) Ammonium chloride NH 4 Cl b) Silver sulfate Ag 2 SO 4 c) Aluminum hydroxide Al(OH)3 d) Calcium phosphate Ca 3(PO 4)2
Things to Notice n n Most complex ions are anions. Ammonium, NH 4+, is the most common complex cation. Several complex ions form a short series of ions. The ions differ only in the number of oxygen atoms: perchorate Cl. O 4 - sulfate SO 42 - chlorate Cl. O 3 - sulfite SO 32 - chlorite Cl. O 2 - hypochlorite Cl. O- nitrate NO 3 - nitrite NO 2 -
n If an ion carries a charge like “-2” or “-3”, a series of related ions can be formed by adding hydrogen cations (H+) while still leaving a net charge: examples: Sulfide: S 2 - hydrogen sulfide: HS- (bisulfide) Sulfate: SO 42 - hydrogen sulfate: (bisulfate) Carbonate: CO 32 - hydrogen carbonate: Phosphate: PO 43 - hydrogen phosphate: (bicarbonate) HSO 4 HCO 3 HPO 42 - dihydrogen phosphate: H 2 PO 4 -
More Formulas with Complex Ions a) Sodium bicarbonate Na. HCO 3 b) Nickel (II) hydrogen sulfide Ni(HS)2 c) Aluminum perchlorate Al(Cl. O 4)3 d) Barium dihydrogen phosphate Ba(H 2 PO 4)2
Hydrated Ionic Compounds n n A HYDRATE is an salt that has water molecules trapped within its crystals. Every hydrate has a certain number of water molecules associated with each formula unit of the ionic compound. The number of water molecules is indicated by using prefixes. mono di tri tetra penta hexa hepta octa nona deca Cu. SO 4 · 5 H 2 O copper (II) sulfate pentahydrate Mg. CO 3 · 10 H 2 O magnesium carbonate decahydrate
Examples of hydrates: n n Write the formulas: copper(II) fluoride tetrahydrate Cu. F 2 · 4 H 2 O calcium nitrate trihydrate Ca(NO 3)2 · 3 H 2 O Write the names: Mg. SO 4 · 7 H 2 O magnesium sulfate heptahydrate Fe. Cl 2 · H 2 O iron (II) chloride monohydrate
Binary Covalent Compounds n n n Covalent compounds are made of two NONMETAL elements sharing valence electrons. There are no ions involved!! Because there are no charges to help us write the formulas of covalent compounds, prefixes are used to indicate the number of each atom present in the formula. CO 2 is named “carbon dioxide” CO is named “carbon monoxide” N 2 O is named “dinitrogen monoxide” SO 3 is named “sulfur trioxide” The prefix, “mono” is never used for the first element in the formula!
Examples of Covalent Naming n n Write the names: SO 2 sulfur dioxide P 4 O 10 tetraphosphorus decoxide Write the formulas: phosphorus pentachloride PCl 5 dinitrogen trioxide N 2 O 3
Binary Acids n n n A simple definition of an “acid” is a substance which produces H+ ions in water. Most acids have hydrogen ions in their formulas. A binary acid composed of a hydrogen cation bonded to one other element: HCl hydrochloric acid HBr hydrobromic acid H 2 S hydrosulfuric acid Binary acids are always named: hydro____ic acid
Oxy-Acids n An acid can also be made of a hydrogen ion bonded to a complex ion. Complex ions whose names end in “ate”: NO 3 - CO 32 - SO 42 - nitric acid: HNO 3 sulfuric acid: H 2 SO 4 carbonic acid: H 2 CO 3 phosphoric acid: H 3 PO 43 - Can you propose a rule for naming oxy-acids with complex ions ending in “ate”?
More Oxy-Acids n Complex ions ending in “ite”: NO 2 - SO 32 - Cl. O- nitrous acid: HNO 2 sulfurous acid: H 2 SO 3 hypochlorous acid: HCl. O chlorous acid HCl. O 2 - Can you propose a rule for naming oxy-acids with complex ions ending in “ite”?
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