If a Weak Acid Is 25% Deprotonated at PH 4

question 39

Multiple Choice

If a weak acid is 25% deprotonated at pH 4, what would the pK_a be?

• A) 3.40
• B) 3.52
• C) 4.48
• D) 4.60
• E) cannot determine from given information

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Definitions:

Endorphins

Endorphins are neurotransmitters in the brain that act as natural painkillers and mood elevators, often released in response to stress and pain.

Morphine

A potent opiate analgesic drug derived from the opium poppy, used to treat severe pain.

Codeine

An opiate used to treat pain, as a cough suppressant, or occasionally in the treatment of diarrhea.

Neurotransmission

The process by which nerve cells (neurons) communicate with each other through the exchange of chemical messengers called neurotransmitters.