Q1. What is the dominant form of benzoic acid at pH 2. Suggest the dominant form...

Q1. What is the dominant form of benzoic acid at pH 2. Suggest the dominant form of caffeine at pH 2.

Q2. This lab uses a C18-reverse phase column. What does the stationary phase consists of? Is it polar or nonpolar?

Q3. Predict whether benzoic acid or caffeine will come out of the C18-reverse phase column first at pH 2.

Q4. To prepare the calibration standard solutions, calculate how much of each stock solution of sodium benzoate and caffeine should be added to each of the 25 mL volumetric flasks (See the procedure).

Q5. What are the peak absorption wavelengths of sodium benzoate and caffeine, respectively?

Expert Solution

Amanda K answered 2 years ago

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