© University of South Carolina Board of Trustees Common Ion Effect MgCO 3 has a K sp = 2.6 x10 −5 in water. What is its solubility in pure water? s = 5.1 x10 −3 M What is its solubility in a 0.30 M MgCl 2 aqueous solution? s = x10 −5 M (quad. eq.) s = x10 −5 M (approx.)

© University of South Carolina Board of Trustees Common Ion Effect: Not so Common MgCO 3 has a K sp = 2.6 x10 −5. What is its solubility in a 0.30 M NaCl solution? MgCO 3 has a K sp = 2.6 x10 −5. What is its solubility in a 0.30 M MgCl 2 solution?

© University of South Carolina Board of Trustees Chapt. 14 Chemical Equilibrium Sec. 7 Will a Precipitate Form?

Will a Precipitate Form? mL of M Na 2 CO 3 and mL of M Ca(NO 3 ) 2 are mixed. Will a precipitate form? ­Identify the most likely precipitate (Table 4.1) ­Find initial concentrations ­ Q vs K sp

© University of South Carolina Board of Trustees Chapt. 15 Acids and Bases Sec. 1 Definitions

© University of South Carolina Board of Trustees Bronsted-Lowry Acids and Bases Acid (A):proton donor Base (B):proton acceptor AH + B  A − + BH + proton transfer H+H+H+H+

© University of South Carolina Board of Trustees Arrhenius vs Bronsted-Lowry Arrhenius ­Acid:Source of H + in water ­Base:Source of OH − in waterBronsted-Lowry ­Acid:Donates H + from a base ­Base:Accepts H + from an acid Lewis ­Sec (skip)

© University of South Carolina Board of Trustees Acids (proton donors) HCl HCl + B  Cl - +HB +

© University of South Carolina Board of Trustees Acids (proton donors) HCl HCl + B  Cl - +HB + NH 4 + NH B  NH 3 + HB +

© University of South Carolina Board of Trustees Acids (proton donors) HCl HCl + B  Cl - +HB + NH 4 + NH B  NH 3 + HB + H 2 SO 4 H 2 SO 4 + B  HSO HB +

© University of South Carolina Board of Trustees Acids (proton donors) HCl HCl + B  Cl - +HB + NH 4 + NH B  NH 3 + HB + H 2 SO 4 H 2 SO 4 + B  HSO HB + HSO 4 - HSO B  SO HB +

© University of South Carolina Board of Trustees Acids (proton donors) HCl HCl + B  Cl - +HB + NH 4 + NH B  NH 3 + HB + H 2 SO 4 H 2 SO 4 + B  HSO HB + HSO 4 - HSO B  SO HB + H 3 O + H 3 O + + B  H 2 O + HB +

© University of South Carolina Board of Trustees Acids (proton donors) HCl HCl + B  Cl - +HB + NH 4 + NH B  NH 3 + HB + H 2 SO 4 H 2 SO 4 + B  HSO HB + HSO 4 - HSO B  SO HB + H 3 O + H 3 O + + B  H 2 O + HB + H 2 O H 2 O + B  OH - + HB +

© University of South Carolina Board of Trustees Acids (proton donors) HCl HCl + B  Cl - +HB + NH 4 + NH B  NH 3 + HB + H 2 SO 4 H 2 SO 4 + B  HSO HB + HSO 4 - HSO B  SO HB + H 3 O + H 3 O + + B  H 2 O + HB + H 2 O H 2 O + B  OH - + HB + Bases (proton acceptor) NH 3 NH 3 + AH  NH A -

© University of South Carolina Board of Trustees Acids (proton donors) HCl HCl + B  Cl - +HB + NH 4 + NH B  NH 3 + HB + H 2 SO 4 H 2 SO 4 + B  HSO HB + HSO 4 - HSO B  SO HB + H 3 O + H 3 O + + B  H 2 O + HB + H 2 O H 2 O + B  OH - + HB + Bases (proton acceptor) NH 3 NH 3 + AH  NH A - OH - OH - + AH  H 2 O + A -

© University of South Carolina Board of Trustees Acids (proton donors) HCl HCl + B  Cl - +HB + NH 4 + NH B  NH 3 + HB + H 2 SO 4 H 2 SO 4 + B  HSO HB + HSO 4 - HSO B  SO HB + H 3 O + H 3 O + + B  H 2 O + HB + H 2 O H 2 O + B  OH - + HB + Bases (proton acceptor) NH 3 NH 3 + AH  NH A - H 2 O H 2 O + AH  H 3 O + + A - OH - OH - + AH  H 2 O + A -

© University of South Carolina Board of Trustees Acids (proton donors) HCl HCl + B  Cl - +HB + NH 4 + NH B  NH 3 + HB + H 2 SO 4 H 2 SO 4 + B  HSO HB + HSO 4 - HSO B  SO HB + H 3 O + H 3 O + + B  H 2 O + HB + H 2 O H 2 O + B  OH - + HB + Bases (proton acceptor) Cl - Cl - + AH  HCl + A - NH 3 NH 3 + AH  NH A - H 2 O H 2 O + AH  H 3 O + + A - OH - OH - + AH  H 2 O + A -

© University of South Carolina Board of Trustees Acids (proton donors) HCl HCl + B  Cl - +HB + NH 4 + NH B  NH 3 + HB + H 2 SO 4 H 2 SO 4 + B  HSO HB + HSO 4 - HSO B  SO HB + H 3 O + H 3 O + + B  H 2 O + HB + H 2 O H 2 O + B  OH - + HB + Bases (proton acceptor) Cl- Cl - + AH  HCl + A - NH 3 NH 3 + AH  NH A - SO 4 2- SO AH  HSO A - H 2 O H 2 O + AH  H 3 O + + A - OH - OH - + AH  H 2 O + A -

© University of South Carolina Board of Trustees Acids (proton donors) HCl HCl + B  Cl - +HB + NH 4 + NH B  NH 3 + HB + H 2 SO 4 H 2 SO 4 + B  HSO HB + HSO 4 - HSO B  SO HB + H 3 O + H 3 O + + B  H 2 O + HB + H 2 O H 2 O + B  OH - + HB + Bases (proton acceptor) Cl- Cl - + AH  HCl + A - NH 3 NH 3 + AH  NH A - HSO 4 - HSO AH  H 2 SO 4 + A - SO 4 2- SO AH  HSO A - H 2 O H 2 O + AH  H 3 O + + A - OH - OH - + AH  H 2 O + A -

© University of South Carolina Board of Trustees Conjugate Acid-Base Pairs AH + B  A - + HB + acidbase conj. base conj. acid

© University of South Carolina Board of Trustees Conjugate Acid HCl HCl + B  Cl - +HB + NH 4 + NH B  NH 3 + HB + H 2 SO 4 H 2 SO 4 + B  HSO HB + HSO 4 - HSO B  SO HB + H 3 O + H 3 O + + B  H 2 O + HB + H 2 O H 2 O + B  OH - + HB + – Base Pairs Cl- Cl - + AH  HCl + A - NH 3 NH 3 + AH  NH A - HSO 4 - HSO AH  H 2 SO 4 + A - SO 4 2- SO AH  HSO A - H 2 O H 2 O + AH  H 3 O + + A - OH - OH - + AH  H 2 O + A -

© University of South Carolina Board of Trustees HCN + H 2 O  CN − + H 3 O + Example: Identify Acids and Bases

© University of South Carolina Board of Trustees HCN + H 2 O  CN − + H 3 O + HCN is the acid H 2 O is the base Example: Identify Acids and Bases

© University of South Carolina Board of Trustees HCN + H 2 O  CN − + H 3 O + CN - is its conjugate base H 3 O + is its conjugate acid HCN is the acidCN - is its conjugate base H 2 O is the baseH 3 O + is its conjugate acid Example: Identify Acids and Bases

© University of South Carolina Board of Trustees HCN + H 2 O  CN − + H 3 O + HCN is the acidCN - is its conjugate base H 2 O is the baseH 3 O + is its conjugate acid CH 3 COO - + H 2 O  CH 3 COOH + OH − Example: Identify Acids and Bases

© University of South Carolina Board of Trustees HCN + H 2 O  CN − + H 3 O + HCN is the acidCN - is its conjugate base H 2 O is the baseH 3 O + is its conjugate acid CH 3 COO - + H 2 O  CH 3 COOH + OH − CH 3 COO − is the base H 2 O is the acid Example: Identify Acids and Bases

© University of South Carolina Board of Trustees HCN + H 2 O  CN − + H 3 O + HCN is the acidCN - is its conjugate base H 2 O is the baseH 3 O + is its conjugate acid CH 3 COO − + H 2 O  CH 3 COOH + OH − CH 3 COOH is its conjugate acid CH 3 COO − is the base CH 3 COOH is its conjugate acid OH − is its conjugate base H 2 O is the acidOH − is its conjugate base Example: Identify Acids and Bases

© University of South Carolina Board of Trustees HNO 2 + H 2 O  NO H 3 O + CH 3 NH 2 + H 2 O  CH 3 NH OH - Students: Identify Acids and Bases

© University of South Carolina Board of Trustees HNO 2 + H 2 O  NO H 3 O + HNO 2 is the acidNO 2 - is its conjugate base H 2 O is the baseH 3 O + is its conjugate acid CH 3 NH 2 + H 2 O  CH 3 NH OH - Students: Identify Acids and Bases

© University of South Carolina Board of Trustees HNO 2 + H 2 O  NO H 3 O + HNO 2 is the acidNO 2 - is its conjugate base H 2 O is the baseH 3 O + is its conjugate acid CH 3 NH 2 + H 2 O  CH 3 NH OH - CH 3 NH 2 is the base CH 3 NH 3 + is its conjugate acid H 2 O is the acidOH - is its conjugate base Students: Identify Acids and Bases

© University of South Carolina Board of Trustees H 2 OH 3 O + HNO 2 + H 2 O  NO H 3 O + H 2 O is the base HNO 2 is the acidNO 2 - is its conjugate base H 2 O is the baseH 3 O + is its conjugate acid H 2 O OH - CH 3 NH 2 + H 2 O  CH 3 NH OH - CH 3 NH 2 is the base CH 3 NH 3 + is its conjugate acid H 2 O is the acid H 2 O is the acidOH - is its conjugate base Students: Identify Acids and Bases

© University of South Carolina Board of Trustees AmphotericHCl HCl + B  Cl - +HB + NH 4 + NH B  NH 3 + HB + H 2 SO 4 H 2 SO 4 + B  HSO HB + HSO 4 - HSO B  SO HB + H 3 O + H 3 O + + B  H 2 O + HB + H 2 O H 2 O + B  OH - + HB +CompoundsCl- Cl - + AH  HCl + A - NH 3 NH 3 + AH  NH A - HSO 4 - HSO AH  H 2 SO 4 + A - SO 4 2- SO AH  HSO A - H 2 O H 2 O + AH  H 3 O + + A - OH - OH - + AH  H 2 O + A -

© University of South Carolina Board of Trustees Amphoteric = Acts as both acid and base HSO B  SO HB + HSO HA  H 2 SO 4 + A -

© University of South Carolina Board of Trustees Amphoteric = Acts as both acid and base HSO B  SO HB + HSO HA  H 2 SO 4 + A - H 2 PO B  HPO HB + H 2 PO HA  H 3 PO 3 + A -

© University of South Carolina Board of Trustees Definitions Proton Acid Base Conjugate AcidConjugate Base Amphoteric

© University of South Carolina Board of Trustees Chapt. 15 Acids and Bases Sec. 2 Water

© University of South Carolina Board of Trustees Autoionization of Water (Amphoteric) base H+H+H+H+ acid H 2 O (l) + H 2 O (l) K w = [H 3 O + ] [OH - ] = 1.0 x (at 24  C)  H 3 O + (aq) + OH - (aq)

© University of South Carolina Board of Trustees p X Notation [OH - ] = 10 -pOH X = 10 -p X p X = - log 10 X pH = - log [H 3 O + ][H 3 O + ] = 10 -pH pOH = - log [OH - ] p K w = - log K w K w = 10 -p K w