1. Alum Lab – Two Week Lab • Hand in to TA: Alum-Pre-lab, Density-Report + GCF’s. • Beverage Can => KAl(SO4)2·12H2O [Alum] • Recycling; Filtration [ Demo ] ; Melting Point. • 2 Al(s) + 2 KOH(aq) + 6 H2O(l)  2 K[Al(OH)4](aq) + 3 H2(g) [Keep Filtrate/Solution] • 2 K[Al(OH)4](aq) + H2SO4(aq)  2 Al(OH)3(s) + K2SO4(aq) + 2 H2O(l) [white lumps] [Heat to Boiling to dissolve] • DO NOT use Methyl Red Indicator. • 2 Al(OH)3(s) + 3 H2SO4(aq)  Al2(SO4)3(aq) + 6 H2O(l) [ excess only if needed ] • K+(aq) + Al3+(aq) + 2 SO42-(aq) +12 H2O(l)  KAl(SO4)2·12H2O(s) [ Gooch Filter precipitate ] • Be sure to pre-weigh filter paper & beaker. Put product in beaker and then locker. • Next week. [ Weigh Alum, % Yield, mp ] • Report due next week. [ Do everything else for report except … ] [ On Warm Hot Plate ] Cool Solution in Ice Bath for ~20 min

2. KAl(SO4)2·12H2O(s)