Acids, Bases, and Buffers 2: Unknown Solutions Overview Getting Started Techniques Procedure FAQ Full Lab Manual Introduction & Goals Chemistry & Background Key Questions Prelab Problems Safety Procedure In Your Write-up Appendix Experiments Index ChemLab Home		Technique Links Burets pH Meter Titration Goals This week you will use the skills and knowledge gained in the last experiment to determine the acid-base character of two unknown samples. You and your partner will be given two different samples that are either an acid, a base, or a buffer. You will devise a procedure to determine what types of solutions you have and what their components are. A list of possible acids and conjugate acids of possible bases is given in the table on page 149 of your manual. Buffers could be composed of any tabulated acid and its conjugate base. Key Questions 1. What happens when you titrate a weak acid solution with a strong base? What will the titration curve look like? Remember last week? 2. What would happen if you titrated a weak acid solution with a strong ACID? What will final pH be? 3. What happens if you titrate a weak base solution with a strong acid? What will the titration curve look like? 4. What would happen if you titrated at weak base solution with a strong BASE? What will final pH be? 5. What happens to pH when you dilute a buffer? A weak acid? A weak base? 6. What is the pH of the titrant solutions? (0.1 M strong acid and base) 7. How is the behavior of a weak acid solution (e.g. 0.1 M acetic acid) different from that of a buffer at acidic pH (e.g. acetic acid/acetate buffer)? Can you point to a region of the acetic acid titration curve that corresponds to both solutions?
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