Effect of ph on uv absorbance of benzoic acid

In summary, the conversation discusses the differences in UV absorbance among various species such as the phenoxide ion, aniline, benzoate ion, and benzoic acid. The source provided suggests that benzoate ion absorbs at a shorter wavelength and with less efficiency than benzoic acid, which the person is trying to understand. The conversation also mentions the impact of pH on dimers of benzoic acid. The person is seeking clarification and assistance in understanding this topic.
  • #1
jethro
2
0
i was recently reading about uv absorbance, and i understand why species such as the phenoxide ion and aniline absorb uv radiation at longer radiation and with more efficiency than their protonated counterparts.
i have spent long hours, however, trying to figure out why a benzoate ion might absorb at a shorter wavelength, and with less efficiency, than benzoic acid.
i have attached the source which suggests that this is true; there is a graph on page 5. my last resort is to say that the source is wrong but i want to make sure... can anyone help?
 

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  • #2
How might dimers of benzoic acid be different at high pH vs. low pH?

http://pubs.acs.org/doi/abs/10.1021/ja00503a016"
 
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  • #3
of course!

...much appreciated, thank you.
 

Related to Effect of ph on uv absorbance of benzoic acid

What is the purpose of studying the effect of pH on UV absorbance of benzoic acid?

The purpose of this study is to understand how the pH of a solution can impact the UV absorbance of benzoic acid. This can provide valuable insights into the behavior of this compound and its potential applications in various industries.

What is the process for measuring the UV absorbance of benzoic acid at different pH levels?

The process involves preparing solutions of benzoic acid at various pH levels, using a spectrophotometer to measure the absorbance of UV light by the solutions, and then analyzing the data to determine the relationship between pH and UV absorbance.

What factors can affect the accuracy of the results in this study?

Some factors that can affect the accuracy of the results include the purity of the benzoic acid used, the calibration of the spectrophotometer, and the consistency of pH measurements.

What can the UV absorbance data reveal about the behavior of benzoic acid at different pH levels?

The UV absorbance data can reveal how the structure of benzoic acid changes as the pH of the solution changes. It can also provide information about the solubility and stability of the compound at different pH levels.

What are the potential implications of this study in the fields of chemistry and materials science?

This study can have implications in understanding the behavior of benzoic acid in various chemical reactions and its potential applications in materials science, such as in the development of UV-blocking materials or in pharmaceutical formulations.

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