CHEM 140
CHEM 171 - Fall 2012Name:
_________________________________Take-Home Worksheet Not to be
turned in Answers on Canvas
1. You add 0.2916 grams of a Metal Hydroxide, M(OH)2, to water
and then titrate using 25.84 mL of a 0.3870 M HNO3 solution. What
is the Metal, M? {H+ + OH H2O}
2.You mix 400.0 mL of a 0.120 M Lead (II) Nitrate with 600.0 mL
of a 0.100 M Sodium Iodide and a yellow Lead (II) Iodide
precipitates. (PbI2 = 461.00 g/mol)Pb(NO3)2(aq) + 2 NaI(aq) PbI2(s)
+ 2 NaNO3(aq)a. How many grams of Lead (II) Iodide can
theoretically form? (think limiting reactant)b. What are [Pb2+],
[Na+], [I], and [NO3] after precipitation is complete (total end
volume = 1000.0 mL)?
__________________ = Limiting Reactant_______________ grams
PbI2
______________ M = [Pb2+]_______________M = [Na+]
________________ M = [I]________________M = [NO3]
3.Assign Oxidation Numbers for each atom in the following
compounds and ions. Again, the oxidation number is per atom (e.g.
H2O has a +1 for Hydrogen, not +2)
Fe2O3: Fe = __ O = __SnCl2 : Sn = __ Cl = __C2H6: C = __ H =
__NH4+ : N = __ H = __MgO2: Mg = __ O = __Cr2O72: Cr = __ O =
__
