9/19/2012 Chapter 6 More on Chemical Compounds Chapter Map Monatomic Ion Names Roots of Nonmetals • Monatomic Cations H hydr- F fluor- – (name of metal) C carb- Cl chlor- • Groups 1, 2, and 3 metals N nitr- Br brom- 3+ 2+ 2+ + • Al , Zn , Cd , Ag P phosph- I iod- – (name of metal)(Roman numeral) • All metallic cations not mentioned above O ox- • Monatomic Anions S sulf- – (root of nonmetal name)ide Se selen- Monatomic Anions Polyatomic Ions Hydride H− fluoride F− Ion Name Ion Name 3− − + − Nitride N chloride Cl NH4 ammonium NO3 nitrate Phosphide P3− bromide Br− OH− hydroxide SO 2− sulfate Oxide O2− 4 − 2− iodide I 2− − Sulfide S CO3 carbonate C2H3O2 acetate 2− 3− selenide Se PO4 phosphate 1 9/19/2012 Polyatomic Ions Recognizing Ionic with Hydrogen Compounds • Metal-nonmetal…binary ionic − • HCO3 hydrogen carbonate compound • HSO − hydrogen sulfate 4 − • HS hydrogen sulfide • HPO 2− hydrogen phosphate 4 − • H2PO4 dihydrogen phosphate • Metal-polyatomic ion • Ammonium-nonmetal or ammonium polyatomic ion Converting Ionic Cation Names Formulas to Names Metals with one name of metal possible charge (Al, • Name Zn, Cd, and Groups 1, – (name of cation) (name of anion) 2, 3) Metals with more than name(Roman numeral) one possible charge (the rest) polyatomic cations name of polyatomic ion (e.g. ammonium) Anion Names Converting Ionic Names to Formulas monatomic anion (root of nonmetal name)ide • Determine the formula, including polyatomic anion name of polyatomic ion charge, for the cation and anion. • Determine the ratio of the ions that yields zero overall charge. 2 9/19/2012 Monatomic Ions Binary Covalent Common Names Naming Binary Covalent Compounds • If the subscript for the first element is –H2O, water greater than one, indicate the subscript –NH , ammonia with a prefix. 3 – We do not write mono- on the first name. –CH , methane – Leave the "a" off the end of the prefixes that 4 end in "a" and the “o” off of mono- if they are placed in front of an element that begins with –C2H6, ethane a vowel (oxygen or iodine). • Follow the prefix with the name of the first –C3H8, propane element in the formula. Naming Binary Prefixes Covalent Compounds mon(o) hex(a) • Write a prefix to indicate the subscript for the second element. di hept(a) • Write the root of the name of the oct(a) second symbol in the formula. tri • Add -ide to the end of the name. tetr(a) non(a) pent(a) dec(a) 3 9/19/2012 Roots of Nonmetals Forms of Binary Covalent Names H hydr- F fluor- • prefix(name of nonmetal) prefix(root of name of nonmetal)ide Cl chlor- C carb- • (for example, dinitrogen pentoxide) N nitr- Br brom- • or (name of nonmetal) prefix(root of P phosph- I iod- name of nonmetal)ide O ox- • (for example, carbon dioxide) S sulf- • or (name of nonmetal) (root of Se selen- nonmetal)ide • (for example, hydrogen fluoride) Writing Binary Arrhenius Acid Covalent Formulas Definition • An acid is a substance that • Write the symbols for the elements + generates hydronium ions, H3O in the order mentioned in the (often described as H+), when name. added to water. • Write subscripts indicated by the • An acidic solution is a solution prefixes. If the first part of the name with a significant concentration of + has no prefix, assume it is mono-. H3O ions. Characteristics of Strong Acid and Water Acids When HCl dissolves in water, hydronium + − Acids have a sour taste. ions, H3O , and chloride ions, Cl , ions form. Acids turn litmus from blue to red. Acids react with bases. 4 9/19/2012 Solution of a Strong Acid Types of Acids • Binary acids have the general formula of HX(aq) – HF(aq), HCl(aq), HBr(aq), and HI(aq) • Oxyacids have the general formula HaXbOc. – HNO3 and H2SO4 • Organic (carbon-based) acids – HC2H3O2 Monoprotic and Acetic Acid Polyprotic Acids • If each molecule of an acid can donate one hydrogen ion, the acid is called a monoprotic acid. • If each molecule can donate two or more hydrogen ions, the acid is a polyprotic acid. • A diprotic acid, such as sulfuric acid, H2SO4, has two acidic hydrogen atoms. • Some acids, such as phosphoric acid, H3PO4, are triprotic acids. Strong and Weak Acids Weak Acid and Water • Strong Acid = due to a completion Acetic acid reacts with water in a reversible reaction with water, generates close reaction, which forms hydronium and acetate ions. + to one H3O for each acid molecule added to water. • Weak Acid = due to a reversible reaction with water, generates + significantly less than one H3O for each molecule of acid added to water. 5 9/19/2012 Solution of Weak Acid Strong and Weak Acids Sulfuric Acid Acid Summary Strong Weak Binary acid hydrochloric acid, hydrofluoric acid H2SO4(aq) + H2O(l) HCl(aq) + H3O (aq) + HSO4 (aq) Oxyacid nitric acid, HNO3 other acids sulfuric acid, H2SO4 with HaXbOc HSO4 (aq) + H2O(l) + 2 H3O (aq) + SO4 (aq) Organic acid none acetic acid, HC2H3O2 Names and Formulas Names and Formulas of Binary Acids for Oxyacids • If enough H+ ions are added to a • Names have the general form of (root)ate polyatomic ion to completely hydro(root)ic acid, such as neutralize its charge, the (root)ic acid is hydrochloric acid. formed. • The formulas are usually followed − – Nitrate, NO3 , goes to nitric acid, HNO3. by (aq), such as HCl(aq). 2− – Sulfate, SO4 , goes to sulfuric acid, H2SO4. (Note the -ur- in the name.) 3− – Phosphate, PO4 , goes to phosphoric acid, H3PO4. (Note the -or- in the name.) 6 9/19/2012 Chemical Nomenclature • General procedure for naming compounds (See Table 5.5 in the text.) – Step 1: Decide what type of compound the name or formula represents. – Step 2: Apply the rules for writing the name or formula for that type of compound. 7 .