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Question 1:

What is the purpose of a buffer solution?

A) To maintain a constant pH
B) To increase the pH of a solution
C) To decrease the pH of a solution
D) To neutralize an acidic solution

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Explanation: The correct answer is A) To maintain a constant pH. A buffer solution is a solution that resists changes in pH when small amounts of acid or base are added to it. It consists of a weak acid and its conjugate base or a weak base and its conjugate acid. The components of a buffer solution work together to maintain the pH of the solution within a certain range.

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Question 2:

Which of the following is an example of a buffer solution?

A) Distilled water
B) Hydrochloric acid
C) Sodium hydroxide solution
D) Acetic acid-sodium acetate solution

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Explanation: The correct answer is D) Acetic acid-sodium acetate solution. Acetic acid-sodium acetate is an example of a buffer solution. It consists of a weak acid (acetic acid) and its conjugate base (sodium acetate). This combination allows the solution to resist changes in pH when acid or base is added.

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Question 3:

Which of the following is true about the pH of a buffer solution?

A) The pH of a buffer solution is always acidic
B) The pH of a buffer solution is always basic
C) The pH of a buffer solution remains constant
D) The pH of a buffer solution changes significantly when acid or base is added

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Explanation: The correct answer is C) The pH of a buffer solution remains constant. A buffer solution is designed to maintain a relatively constant pH when small amounts of acid or base are added. It achieves this by having a pair of components that can react with any added acid or base to minimize the change in pH.

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Question 4:

Which of the following is a commonly used buffer system in biological systems?

A) Phosphate buffer system
B) Sulfate buffer system
C) Nitrate buffer system
D) Chloride buffer system

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Explanation: The correct answer is A) Phosphate buffer system. The phosphate buffer system is commonly used in biological systems to maintain a constant pH. It involves the equilibrium between dihydrogen phosphate (H2PO4-) and hydrogen phosphate (HPO42-), which can accept or donate protons to resist changes in pH.

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Question 5:

Which of the following pH values is considered optimal for most biological processes?

A) pH 1
B) pH 7
C) pH 14
D) pH 7.4

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Explanation: The correct answer is D) pH 7.4. pH 7.4 is considered optimal for most biological processes. It is the pH value found in the human body, particularly in the blood. Deviations from this pH can significantly affect enzyme activity and cellular function.