A Certain Carboxylic Acid Has a K_a of 5

question 111

Multiple Choice

A certain carboxylic acid has a K_a of 5.1 × 10^-7. What is the ratio of the ratio of the deprotonated to the protonated form, respectively, at physiological pH of about 7.4? Assume the following general reaction. HA(aq) + H₂O(l) → H₃O⁺(aq) + A^-(aq)

• A) 13 : 1
• B) 1 :13
• C) 100 : 1
• D) 1 : 100

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Definitions:

Ego

The largely conscious, “executive” part of personality that, according to Freud, mediates among the demands of the id, the superego, and reality. The ego operates on the reality principle, satisfying the id’s desires in ways that will realistically bring pleasure rather than pain.

Oedipus Complex

According to Freud, a boy’s sexual desires toward his mother and feelings of jealousy and hatred for the rival father.

Pleasure Principle

A concept in psychoanalytic theory referring to the instinctual seeking of pleasure and avoiding of pain to satisfy biological and psychological needs.

Reality Principle

A psychoanalytic concept referring to the ability of the mind to assess the external world and act upon it accordingly, balancing with the pleasure principle.