The PK_a of a Weak Acid Was Determined by Measuring

question 158

Multiple Choice

The pK_a of a weak acid was determined by measuring the pH of a solution containing the weak acid at 0.40 M and its conjugate base at 0.60 M. The measured pH was 7.8. What is the pK_a of the
Weak acid?

• A) 8.0
• B) 7.8
• C) 7.6
• D) 7.0
• E) 7.4

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Definitions:

Plasma Volume

The volume of plasma, the liquid component of blood without the cells, important for maintaining blood pressure and volume.

ADH Levels

Refers to the concentration of antidiuretic hormone in the blood, which regulates water balance in the body by affecting the kidneys.

Cerebral Arterial Circle

Also known as the Circle of Willis, it is a ring of interconnected arteries at the base of the brain that provides collateral blood flow between the anterior and posterior circulations.

Arteries

Blood vessels that carry oxygenated blood away from the heart to the body's tissues, except for the pulmonary arteries that carry deoxygenated blood to the lungs.