Introduction The goals of this experiment were to determine periodic trends in solubility of group 2 metals. The other goal was to use our knowledge of solubility’s to identify cations present in a single unknown Xe and double unknown XXe. I have hypothesized that the solubility of group 2 elements will decrease as we progress down the periodic table .I think that this will happen because of effective nuclear charge (Zeff) which is the key trend of the periodic table which states how effective a nucleus is at bringing electrons towards it. So if the Zeff is decreasing as we go down the periodic table the ability for an element to be soluble decreases as well because the atoms cannot hold onto their own electrons, which in turn allows for other atoms to take over.
Materials and methods
* Well plate
* Cation liquid solutions (Mg2+,Ca2+ ,Sr2+,Ba2+)
* Anion aqueous solutions [(SO4)2-,(c2O4)2-,(CrO4)2-,(NO3)-,(OH)-,(CO3)2-] * Safety equipment (goggles and aprons)
* Data sheet with chart
* Balanced chemical formula sheet
* Bunsen burner
1. Put on safety equipment
2. Get well plate from front desk
3. Go back to lab station , and place two drops of each cation into designated well plate 4. Drop anion into respective cation solution
5. Wait 5 minutes allowing for precipitates to form
6. Record observations on to provided data chart
7. Conduct same steps 1-6 for to unknowns
8. Conduct flame test for XXe to see what cation it is by using Bunsen burner and dipping popsicle stick into XXe the place stick over fire observing what color flame is displayed...