1. Creating a Positive Learning Environment for Everyone
Be respectful of your classmates
Save conversation for clicker portions of lecture
Put cell phones in “airplane” mode
Turn off tablets
Close laptops

2. Announcements
Electronic Homework due Monday, 10/16 (Type I) and Wednesday, 10/18 (Type II) by 7:00pm
Prelecture assignments, textbook HW, and lab write-up due as usual

3. Clicker #1 Which of the three solutions is the most concentrated?
A) Solution #1
B) Solution #2
C) Solution #3
D) The concentrations are the same.

4. Molarity
Left: 2 Molar Solution
Right: 0.5 Molar Solution

5. Clicker #2
You add mL of water to mL of a 2.00 M sugar solution. How many of the following will change?
I. total volume of the solution
II. moles of solute in the solution
III. mass of solute in the solution
IV. concentration of the solution
V. number of solute molecules in the solution
A) 1
B) 2
C) 3
D) 4
E) 5

6. Solution Problem #1
You have 1.00 mol of sugar in mL of solution. Calculate the concentration in units of molarity.

7. Solution Problem #2
You have a 2.50 M sugar solution. Calculate the number of moles of sugar in mL of this solution.

8. Solution Problem #3
You have a 10.0 M sugar solution. What volume of this solution do you need to have 2.00 mol of sugar?

9. Clicker #3
If 200. mL is removed from the original 10.0 M solution, what is the concentration of the remaining (original) solution?
A) M
B) 1.00 M
C) 2.00 M
D) 8.00 M
E) 10.0 M

10. Solution Problem #4
Problem #4: Assume that Kool-aid powder consists primarily of sugar (C6H12O6) and water. If you have a container of Koolaid containing 189 grams of sugar and that Kool-aid has a concentration of 0.70 M, what volume of Kool-aid can be made?

11. Solution Problem #5
You add mL of water to mL of a 4.00 M sugar solution. Calculate the concentration of the new solution in units of molarity. (Assume the volumes are additive.)

12. Clicker #4
Do you predict that the concentration of the 4.00 M sugar solution will increase, decrease, or stay the same?
A) increase
B) decrease
C) stay the same

13. Solution Problem #6
Consider separate solutions of NaOH and KCl made by dissolving equal masses of each solute in equal volumes of solution. Which solution has the greater concentration?

14. Clicker #5
Without using a calculator, which solution has the greater concentration?
MM of NaOH = g/mol
MM of KCl = g/mol
A) KCl
B) NaOH