Shayne - Friday, 2/18

I. We picked up two sheets at the beginning of class - (Molarity 2 and Reaction Stability 1)

II. We went through the Molarity 2 notes:

EXAMPLES:

1.) What will be actually present in the solution when each of the following is added to water?

a. KCL ----------> K+ (aq) plus Cl- (aq)
b. NaNO3 ----------> Na+ (aq) plus NO3- (aq)
c. C2H6O ----------> C2H6O (aq)

3.) Calculate the mlarity (M) of the following solutions. (M = Mol/L)

a. M = 0.0346 Mols/0.250 Liters = 0.138M
b. (405 g NiCl2 X 1 mol NiCl2)/129.59 g NiCl2 = 3.12524 mols NiCl2
M = 3.12524 Mols/7.54 Liters = 0.414M
c. (22.57 g H2SO4 X 1 mol H2SO4)/98.09 g H2SO4 = 0.23009 mols H2SO4
100 Ml = 0.1 L so.....
M = 0.23009 Mols/0.1 L = 2.301M

5.) Calculate the mass of the solute present in the following solutions.

a. Mol = M x L so...
0.125M x 0.200L = (0.25 Mols Kbr x 119 g KBr)/1 Mol KBr = 2.98 g KBr
b. Mol = M x L so...
Mol = 0.150M x 0.1L
(0.015 Mols Na2SO4 x 126.05 g Na2SO4)/1 mol Na2SO4 = 1.89 g Na2SO4

III. We took a lab test in groups of two, having to make a solution of 0.15M of NaCl and show calculations