Blood is buffered by carbonic acid and the bicarbonate ion. Normal blood plasma is 0.024 M in HCO₃^- and 0.0012 M H₂CO₃ (pK_a1 for H₂CO₃ at body temperature is 6.1).
a. What is the pH of blood plasma?

검증된 단계별 안내

Identify the components of the buffer system: carbonic acid (H_2CO_3) and bicarbonate ion (HCO_3^-).

Use the Henderson-Hasselbalch equation for buffer solutions: \( \text{pH} = \text{pK}_a + \log \left( \frac{[\text{A}^-]}{[\text{HA}]} \right) \), where \([\text{A}^-]\) is the concentration of the base (HCO_3^-) and \([\text{HA}]\) is the concentration of the acid (H_2CO_3).

Substitute the given concentrations into the equation: \([\text{A}^-] = 0.024 \text{ M}\) and \([\text{HA}] = 0.0012 \text{ M}\).

Substitute the given \(\text{pK}_a\) value into the equation: \(\text{pK}_a = 6.1\).

Calculate the pH using the equation: \( \text{pH} = 6.1 + \log \left( \frac{0.024}{0.0012} \right) \).

비슷한 문제에 대한 검증된 영상 답변:

이 영상 해법은 위 문제에 도움이 된다고 튜터들이 추천한 것입니다.

영상 길이:

도움이 되었나요?

주요 개념

질문에 올바르게 답하기 위해 반드시 이해해야 하는 핵심 개념들은 다음과 같습니다.

Buffer Systems

Buffer systems are solutions that resist changes in pH upon the addition of small amounts of acid or base. In biological systems, buffers maintain the pH within a narrow range, which is crucial for proper physiological function. The bicarbonate buffer system, involving carbonic acid (H2CO3) and bicarbonate ion (HCO3-), is particularly important in regulating blood pH.

Henderson-Hasselbalch Equation

The Henderson-Hasselbalch equation relates the pH of a buffer solution to the concentration of its acidic and basic components. It is expressed as pH = pKa + log([A-]/[HA]), where [A-] is the concentration of the base (bicarbonate) and [HA] is the concentration of the acid (carbonic acid). This equation is essential for calculating the pH of buffered solutions, such as blood plasma.

pKa and Acid-Base Equilibrium

pKa is the negative logarithm of the acid dissociation constant (Ka) and indicates the strength of an acid in solution. A lower pKa value signifies a stronger acid that dissociates more readily. In the context of the bicarbonate buffer system, the pKa of carbonic acid (6.1) helps determine the pH of blood plasma by indicating the equilibrium between carbonic acid and bicarbonate ions.

Blood is buffered by carbonic acid and the bicarbonate ion. Normal blood plasma is 0.024 M in HCO3- and 0.0012 M H2CO3 (pKa1 for H2CO3 at body temperature is 6.1).a. What is the pH of blood plasma?