ACIDS, BASES,

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ACIDS, BASES, SALTS
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Properties of Acids

• sour taste
• electrolytes
• - aqueous solns conduct electric current
• react with bases to form water and salt
  (neutralization reaction)
• react with most metals to produce H2(g)
• acids turn litmus paper red

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Electrolyte

• substance that dissolves in H2O to produce soln
  that conducts electric current
• acids, bases, salts are electrolytes form
  ions in H2O
• HCl(s) ? H1(aq) Cl-1(aq)
• NaOH(s) ? Na1(aq) OH-1(aq)
• NaCl(s) ? Na1(aq) Cl-1(aq)

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Which metals react with acids?

• See Table J
• All metals above H2 react with acids
• Cu, Ag, and Au do not react with acids

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2HCl Mg ? MgCl2 H2

• Mg above H2 so reaction proceeds
• single replacement reaction occurs

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Properties of Bases

1. bitter taste
2. slippery or soapy feeling
3. Electrolytes
4. react with acids to produce water and salt
5. bases turn litmus paper blue

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Formula of Acid

• 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

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Formula of Base

• Format MOH
• where M is metal
• Ex NaOH, Ca(OH)2
• exception NH3 and NH41
• CH3OH is NOT a base. WHY?

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Identify the Electrolytes

• NaCl
• C2H5OH
• H2SO4
• NaOH
• C6H12O6
• CaI2
• HF
• Mg(OH)2
• C3H7OH

• CCl4
• HNO3
• C5H12
• K3PO4
• CH3OCH3
• LiOH
• HI
• (NH4)2SO4
• C12H22O11

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Acid, Base, or Neutral?

• all H2O contains some H1 and some OH-1 ions
• pure H2O concentrations very low
• neutral solution H1 OH-1
• acidic solution H1 gt OH-1
• basic solution OH-1 gt H1

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Water self-ionization

• H2O(l) H2O(l) ? H3O1(aq) OH-1(aq)
• H3O1 hydronium ion
• OH-1 hydroxide ion
• H2O(l) ? H1(aq) OH-1(aq)
• H1 and H3O1 used interchangeably
• H1 called proton or hydrogen ion

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Arrhenius Acid

• substance that contains hydrogen ionizes to
  produce H1 ions in (aq) soln
• HCl(g) ? H1(aq) Cl-1(aq)
• HNO3 ? H1(aq) NO3-1(aq)

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Arrhenius Base

• substance that contains hydroxide group ionizes
  to produce OH-1 ions in (aq) soln
• NaOH(s) ? Na1(aq) OH-1(aq)

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Arrhenius Salt

• electrolyte where H1 not only () ion and OH-1
  not only (-) ion formed in aqueous solution
• Ex NaCl, CaBr2,KNO3, NH4I

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Salts in Water (ionic compounds)

• NaCl(s) ? Na1(aq) Cl-1(aq)
• CaBr2(s) ? Ca2(aq) 2Br-1(aq)
• KNO3(s) ? K1(aq) NO3-1(aq)
• NH4I(s) ? NH41(aq) I-1(aq)

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Arrhenius Model has limitations

• Dont always use H2O as solvent
• Arrhenius model only applies when H2O is solvent
• Doesnt explain all cases
• NH3 (base) doesnt contain OH-1 but it produces
  OH-1
• NH3(g) ? NH41(aq) OH-1(aq)

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Alternate Theory Bronsted-Lowry

• Acid is a proton donor
• All Arrhenius acids Bronsted-Lowry Acids
• H1
• HX(g) H2O(l) ? H3O1 X-1
• H1 forms molecule-ion bond with water molecule ?
  H3O1 (hydronium ion)

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Bronsted-Lowry Acids
H1

• HCl H2O ? H3O1 Cl-1
• HNO3 H2O ? H3O1 NO3-1
• H2SO4 H2O ? H3O1 HSO4-1
• HSO4-1 H2O ? H3O1 SO4-2

H1
H1
H1
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Bronsted-Lowry Base

• Base is proton acceptor
• OH-1 is base
• H1 OH-1 ? H2O
• not restricted to aqueous solution
• NH3 H2O ? NH41 OH-1
• NH3 is a base!

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Amphoteric

• substance that acts as both acid base
• H2O is amphoteric
• HX(g) H2O(l) ? H3O1 X-1
• (base)
• NH3 H2O ? NH41 OH-1
• (acid)

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Naming Acids Bases
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Naming Binary Acids

• Hydro stem of nonmetal ic
• HF ?
• HCl ?
• H2S ?

Hydrofluoric acid
Hydrochloric acid
Hydrosulfic acid
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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

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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

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Naming Bases

• Name the metal hydroxide
• NaOH ?
• Ca(OH)2 ?
• Mg(OH)2 ?

Sodium hydroxide
Calcium hydroxide
Magnesium hydroxide