A Buffer Is Prepared by Combining 25 ML of 0

question 18

Multiple Choice

A buffer is prepared by combining 25 mL of 0.50 M NH₃(aq) with 25 mL of 0.20 M HCl.What is the pH of the buffer? (K_a (NH₄⁺) = 5.6 × 10−¹⁰)

• A) 7.76
• B) 8.00
• C) 8.86
• D) 9.43
• E) 9.65

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Definitions:

Psychological State

The mental condition of a person at a given time, which encompasses emotions, thoughts, and feelings.

Physiological State

The condition of normal function or activity of the body and its systems, often influenced by factors like health, genetics, and environment.

Drive

An aroused state that occurs because of a physiological need.

Optimum Arousal Theory

The theory that individuals perform best and are most productive at a moderate level of arousal, rather than at lower or higher levels.