ACIDS, ACIDS BASES, BASES & SALTS Properties of Acids 1. Sour taste 2. Electrolytes: - aqueous solns conduct an electric current
3. React with bases to form water and a salt (Neutralization Reaction) 4. React with most metals to produce H2(g) 5. Acids turn litmus red Electrolyte Substance that dissolves in H2O to produce a solution that conducts an
electric current Acids, bases, & salts are electrolytes form ions in H2O NaCl(s) Na+1(aq) + Cl-1(aq) Which metals react with acids? See Table J All metals above H2 react with acids
Cu, Ag, and Au do not react with acids 2HCl + Mg MgCl2 + H2 Mg above H2 so reaction proceeds Single replacement reaction Properties of Bases 1.
2. 3. 4. Bitter taste Slippery or soapy feeling Electrolytes React with acids to produce water and a salt
5. Bases turn litmus blue Formulas of Acids Format: HX where X = nonmetal (F, Cl, Br, I) or X = negative polyatomic ion Some acids have 2 or 3 Hs Ex: HF, H2S, H3PO4
Formulas of Bases Format: MOH where M is a metal Ex: NaOH, OH Ca(OH) OH 2 Exception: NH3 and NH4+1
CH3OH is NOT a base. WHY? Identify the Electrolytes Yes - S NO C2H5OH CCl4 NO
Yes - A NaOH Yes - B C5H12 NO NaCl H2SO4
HNO3 Yes - A K3PO4 Yes - S C6H12O6 CH3OCH3 NO CaI2
LiOH Yes - B NO Yes - S HF Yes - A HI Yes - A
Mg(OH)2 Yes - B (NH4)2SO4 Yes - S C3H7OH NO C12H22O11 NO
Acid, Base, or Neutral? all H2O contains some H+1 and some OH-1 ions pure H2O: concentrations very low Neutral solution: [H+1] = [OH-1] Acidic solution: H+1 > OH-1 Basic solution: OH-1 > H+1
Water & self-ionization H2O(l) + H2O(l) H3O+1(aq) + OH-1(aq) H3O+1 = hydronium ion OH-1 = hydroxide ion H2O(l) H+1(aq) + OH-1(aq) H+1 and H3O+1 used interchangeably H+1 called proton or hydrogen ion Self-ionization of water
Arrhenius Acid Substance that contains hydrogen & ionizes to produce H+1 ions in aqueous solution HCl(g) H+1(aq) + Cl-1(aq) HNO3 H+1(aq) + NO3-1(aq) Arrhenius Base
substance that contains hydroxide group & ionizes to produce OH-1 ions in aqueous solution NaOH(s) Na+1(aq) + OH-1(aq) Arrhenius Salt Electrolytes where H+1 not only positive ion and OH-1 not only negative ion formed in aqueous
solution Ex: NaCl, CaBr2,KNO3, NH4I Salts in Water (ionic compounds) NaCl(s) Na+1(aq) + Cl-1(aq) CaBr2(s) Ca+2(aq) + 2Br-1(aq) KNO3(s) K+1(aq) + NO3-1(aq) NH4I(s) NH4+1(aq) + I-1(aq)
Arrhenius Model has limitations Dont always use H2O as solvent Arrhenius model only applies when H2O is solvent Doesnt explain all cases: NH3 doesnt contain OH-1 but it produces OH-1 Alternate Theory: Bronsted-Lowry Acid = a proton donor
All Arrhenius acids = Bronsted-Lowry Acids HX(g) + H2O(l) H3O+1 + X-1 H+1 forms molecule-ion bond with water molecule H3O+1 (hydronium ion) Bronsted-Lowry Acids HCl + H2O H3O+1 + Cl-1 HNO3 + H2O H3O+1 + NO3-1 H2SO4 + H2O H3O+1 + HSO4-1
HSO4-1 + H2O H3O+1 + SO4-2 Bronsted-Lowry Base Base = proton acceptor OH-1 is a base H+1 + OH-1 H2O Not restricted to aqueous solution NH3 + H2O NH4+1 + OH-1 NH3 is a base!
Bronsted-Lowry Acids & Bases Amphoteric Substance that acts as both acid & base H2O is amphoteric HX(g) + H2O(l) H3O+1 + X-1 (base) NH3 + H2O NH4+1 + OH-1
(acid) Water is amphoteric! Naming Acids & Bases Naming Binary Acids Hydro + stem of nonmetal + ic
HF = ? HCl = ? H2 S = ? Hydrofluoric acid Hydrochloric acid Hydrosulfic acid Naming Ternary Acids
Name derived from polyatomic anion (see Table E) Replace ite with ous , add acid HNO2 is nitrous acid Replace ate with ic, add acid HNO3 is nitric acid Ternary Acids polyatomics with S and P, make stem long again
H3PO4 = phosphoric acid, not phosphic acid H2SO4 = sulfuric acid, not sulfic acid H2SO3 = sulfurous acid, not sulfous acid SEE TABLE K Naming Bases Name the metal + hydroxide NaOH = ?
Ca(OH)2 = ? Mg(OH)2 = ? Sodium hydroxide Calcium hydroxide Magnesium hydroxide
