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At two points we added a type of salt to the extraction. One was potassium acetate (Kac) and the other was ammonium acetate (AA). Each type of salt is used at a different point in the protocol. Why do you do this and what purpose does each one serve it serve?

User BobDroid
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Final answer:

Potassium acetate and ammonium acetate are used in extractions for their pH-adjusting properties and precipitation ability, respectively. Potassium acetate might raise pH when added to a weak acid, whereas ammonium acetate's ion properties typically neutralize each other, maintaining a neutral pH.

Step-by-step explanation:

The use of different types of salt in an extraction protocol can serve various purposes depending on the properties of the ions in the salt. Potassium acetate (Kac) could be used to adjust the pH or to participate in a reaction depending on its anion and cation properties.

Ammonium acetate (AA), on the other hand, features an ammonium ion that can lower the pH and an acetate ion that can raise the pH; however, in the case of ammonium acetate, the two effects typically cancel out, resulting in a neutral solution.

In protein purification protocols, ammonium acetate is often utilized to precipitate proteins due to its ability to neutralize and dehydrate proteins, which makes them precipitate out of the solution. The other salt, potassium acetate, might be used to form the salt of an acid following basic hydrolysis, which would generally occur during an extraction process.

Understanding the behavior of these salts in solution, such as their tendency to form weak acids or bases that affect the pH, helps in manipulating the conditions of an experiment to achieve desired outcomes such as separation or identification of compounds. For example, the addition of a salt like potassium acetate could lead to a higher pH if it provides a base that reacts with the weak acid in the solution.

User DonP
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