Sami Mayhew
Chemistry AP
11-18-08
Titration of and Acid With a Base
Purpose: The purpose is to use burets to accurately measure volumes of a solution. I will also be learning how to learn to recognize the end point of a titration. I’ll be learning to describe the procedure for standardizing a solution and determine the molarity of a base.
Materials: -0.50 M HCl -unknown molarity of NaOH
-50 mL buret -phenolphthalein indicator
-3 dry beakers -ring stand
-wash bottle -125 mL Erlenmeyer flask
-buret clamp
Safety: You must wear goggles. Do not touch any of the chemicals directly. Let your supervisor know as soon as possible if there are any spills. Do not wear expensive clothing on lab day. Notify your supervisor if there is any broken glass, and they will dispense of it appropriately.
Procedure:
1. Label your three beakers: Acid beaker, Base beaker, and Acid Waste beaker
2. Test to make sure your buret does not leak by using distilled water in the buret first. Once you have determined there is no leakage, dispose of distilled water in the sink.
3. Make sure the buret is closed and using one of your beakers, pour about 5 mL of HCl to rinse the sides of the ENTIRE buret. Then pass it through the tip into a waste beaker. Repeat twice.
4. Fill the buret to just past the 0 mL mark with the standard HCl solution. Let acid run through the tip into the acid waste beaker until it is just below the 0 mL mark or until there are NO BUBBLES in the tip.
5. Record the starting volume in your data table.
6. Measure about 9-9.9 mL of the unknown NaOH and record this volume under Trial 1. Be aware of significant digits. Be sure to ask if you are not sure if you have the right amount. Pour this into your clean Erlenmeyer flask. Record the starting volume in your data table.
7. Add distilled water until the liquid covers the entire bottom of the flask.
8. Add two drops of phenolphthalein.
9. Place a plain, white sheet of paper under...