Post on 04-Jan-2016
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Lesson 2Ion
Concentration + Formulas
Ion concentrations in solutions
• Since salts will dissociate into ions when dissolved, we must learn how to calculate ion concentrations in a solution.– very similar to our Equilibrium calculations
from unit 2. – we still need mole ratios from the equation.
What is the concentration of each ion in 2.0 L of a 0.300 M AlCl3 solution?
0.300 M 0.300 M 0.900 M
AlCl3(s) Al3+ + 3Cl-
Try: What is the concentration of all ions present in a saturated solution of Ag2CO3 having a concentration of 1.2 x 10 -4 M?
What is the concentration of each ion in the solution formed by dissolving 80.0 g of CaCl2 in 600.0 mL of water?
1.20 M1.20 M
CaCl2 Ca2+ + 2Cl-
0.600 L
111.1 g
1 mole 80.0 g x
Molarity = moles L
= 1.20 M
2.40 M
Dilutions!If 5.0mL of 0.020 M Cl-1 is added to 15.0 mL of 0.012 M Br-1, what is the
molarity of the Cl-1 and Br-1 ions in the mixture?
Try…If 4.0mL of 0.1M I-1 is added to 16.0 mL of 0.02 M Cl-1, what is the molarity of the Cl-1 and I-1 ions in the mixture?
If 40.0 mL of 0.400 M AlCl3 solution is added to 60.0 mL of 0.600 M CaCl2
solution, what is the resulting concentration of all ions?
[Cl-] = 0.480 + 0.720 M = 1.200 M
AlCl3 Al3+ + 3Cl-
0.480 M0.160 M0.400 M40.0 x
100.0
CaCl2 Ca2+ + 2Cl-
0.600 M 60.0 x
100.0
0.360 M 0.720 M
Try…If 30.0 mL of 0.300 M AlBr3 solution is added to 70.0 mL of 0.700 M CaBr2
solution, what is the resulting concentration of all ions?
If the [Cl-] = 0.600 M, calculate the number of grams AlCl3 that would be
dissolved in 3.00 L of water.
AlCl3 Al3+ + 3Cl-
0.200 M 0.200 M 0.600 M
= 80.1 gx 133.5 g
1 mole
0.200 mole
1 L
3.00 L x
Try…If the [Cl-] = 0.200 M, calculate the number of grams MgCl2 that
would be dissolved in 2.00 L of water.
Writing formula equationcomplete ionic equation and
net ionic equations
Write the formula, complete, and net ionic equation for the reaction which occurs when 0.2 M solutions of Pb(NO3)2 (aq) and FeCl3(aq) are mixed.
Try: Write the formula, complete, and net ionic equation for the reaction which occurs when 0.2 M solutions of magnesium sulphide
and strontium hydroxide are mixed.
Homework
Hebden: pg. 78 #12, 13,14 pg. 81 #18, 19, and 20 (a, c, f, h)