Assuming Equal Concentrations of Conjugate Base and Acid, Which One

question 107

Multiple Choice

Assuming equal concentrations of conjugate base and acid, which one of the following mixtures is suitable for making a buffer solution with an optimum pH of 4.6-4.8?

• A)CH₃COO₂Na / CH₃COOH (K_a = 1.8 × 10^-5)
• B)NH₃ / NH₄Cl (K_a = 5.6 × 10^-10)
• C)NaOCl / HOCl (K_a = 3.2 × 10^-8)
• D)NaNO₂ / HNO₂ (K_a = 4.5 × 10^-4)
• E)NaCl / HCl

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Definitions:

Entrained Circadian Rhythm

The synchronization of the body's natural circadian rhythms (sleep-wake cycle and other biological processes) with the environment, such as the light-dark cycle.

Blind

Blindness is the condition of lacking visual perception due to physiological or neurological factors.

Faster

Operating or moving at high speed or more quickly than is usual, often used to compare the speed or efficiency of processes, objects, or people.

Light Pollution

Exposure to artificial light that changes activity patterns and so disrupts circadian rhythms.