Need P. Tables, Calculators, and Notebooks for review today! What: Calculate molarity and volume of dilutions. RWC -3.2f/g, 4d How: Given desired concentration of solution, generate P/A procedure describing steps to prepare the solution 2 ways, via direct massing and dilution of stock solution. Why? Written assessment tomorrow and Lab Assessment on Friday!

Choose your formula worksheet Choose your formula and solve the problems on the right hands side! SHOW ALL WORK and UNITS UNITS UNITS!! Check at the end… will be turning them in!

Solutions and Dilutions Closing the Loop Game How to play: Each person has a problem and an answer. Person with the  reads their question to the team, EVERYONE ANSWERS on the back of their paper. Person with that answer on the right hand side then reads the next question. Tape together the strips as you go to reveal a very wise quote on the back at the end. 1st team to tape together correctly WITH ALL WORK SHOWN FOR EVERYONE wins!

Choose your DOL How do you feel? Level 1 for “not so sure” people Level 2 for “I’ve got this” people

Lab Assessment information Tomorrow, when you walk in you will be charged with the following task: We will give you a desired concentration of a specific solution and a set of materials. You will be asked to make this concentration 2 ways: 1. Produce the solution via DIRECT MASSING of solute. 2. Produce the solution via DILUATION of a STOCK SOLUTION.

So lets practice we want a 2M NaCL Solution. Available to you are the following items: Solid NaCl 5M Stock NaCl solution Small cups for massing solids Graduated cylinder Scales Distilled Water

We will make our 2M solution 2 ways and then compare their concentrations using the LabPro Colorimeter Method #1: Direct massing of solute 1. Use the molarity formula to calculate the amount in grams of solute to add to 50mL of our solution. 2. Mass the solute. 3. Pour out 25mL of distilled water. 4. Mix the two in a beaker. 5. Label with DIRECT MASSING – 2M NaCl

Production through Dilution!! Method #2: Dilution of Stock Solution 1. Use the dilution formula to calculate the volume of stock solution needed to produce your 2M NaCl solution. 2. Pour out the appropriate volume of stock solution. 3. Dilute the solution to 25mL with distilled water. 4. Label the beaker DILUTION -2M NaCl

So, theoretically we should have the same concentration in both beakers, right? We will use the mini LabPro’s to test the concentration of each of the product solutions, and use a calibration graph to get our EXEPERIMENTAL concentrations.

Formula for % Error % error = (theoretical – actual)/theoretical * 100 So for our procedure, what is the theoretical? 1. 2M 2. 100mL 3. 50mL Calculate your percent error for EACH of these values!!

Molarity Millionaire

Write out the procedure to produce the following solution 2 ways. Produce 100mL of a 3.25M KOH solution using the following materials. Solid KOH Distilled Water Graduated Cylinder Beakers Scales Small massing cups 5.4M Stock KOH Solution