precipitation equations

• [Cu(H2O)6 ]2+ (aq)

  blue solution makes blue ppt

  >[Cu(H2O)6 ]2+ (aq) + 2OH- (aq)  Cu(H2O)4 (OH)2 (s) + 2H2O (l)

  >Cu2+ (aq) + 2OH- (aq)  Cu(OH)2 (s)
• [Mn(H2O)6 ]2+ (aq)

  v. pale pink solution makes pale brown ppt

  >[Mn(H2O)6 ]2+ (aq) + 2OH- (aq)  Mn(H2O)4 (OH)2 (s) + 2H2O (l)

  >Mn2+ (aq) + 2OH- (aq)  Mn(OH)2 (s)
• [Fe(H2O)6 ]2+ (aq)

  green solution makes green ppt

  >[Fe(H2O)6 ]2+ (aq) + 2OH- (aq)  Fe(H2O)4 (OH)2 (s) + 2H2O (l)

  >Fe 2+ (aq) + 2OH- (aq)  Fe(OH)2 (s)
• [Fe(H2O)6 ]3+ (aq)


  yellow/brown solution makes brown ppt

  >[Fe(H2O)6 ]3+ (aq) + 3OH- (aq)  Fe(H2O)3 (OH)3 (s) + 3H2O (l)

  >Fe3+ (aq) + 3OH- (aq)  Fe(OH)3 (s)
• [Cr(H2O)6 ]3+ (aq)


  green solution makes green ppt

  >[Cr(H2O)6 ]3+ (aq) + 3OH- (aq) Cr(H2O)3 (OH)3 (s) + 3H2O (l)

  >Cr3+ (aq) + 3OH- (aq) Cr(OH)3 (s)
• [Mn(H2O)6 ]2+ (aq) when ammonia is added 


  [Mn(H2O)6 ]2+ (aq) + 2NH3 (aq)  Mn(H2O)4 (OH)2 (s) + 2NH4+
• [Fe(H2O)6 ]3+ (aq) when ammonia is added

  [Fe(H2O)6 ]3+ (aq) + 3NH3 (aq)  Fe(H2O)3 (OH)3 (s) + 3NH4+ (aq)