Quiz on Water, pH & Buffering Systems in Biochemistry

What is the bond angle between hydrogen atoms in a water molecule?

• 120°

• 180°

• 104°

• 90°

What is the pH of pure water at 25°C?

• 8.0

• 7.0

• 9.0

• 6.0

Which of the following is a strong acid?

• Acetic acid

• Hydrochloric acid

• Ammonium hydroxide

• Sodium bicarbonate

What does a pH of 3 indicate about a solution?

• Basic

• Neutral

• Acidic

• Alkaline

What is the primary role of buffers in biological systems?

• Dissolve nutrients

• Increase temperature

• Resist pH changes

• Enhance enzyme activity

Which of the following is a characteristic of water's molecular structure?

• V-shaped geometry

• Linear configuration

• Square planar

• Cylindrical shape

What is the effect of temperature on the pH of pure water?

• pH fluctuates randomly

• pH increases with temperature

• pH decreases with temperature

• pH remains constant

What is the Henderson-Hasselbalch equation used for?

• Measuring temperature changes

• Determining buffer pH

• Assessing ion concentration

• Calculating enzyme activity

How does bicarbonate function in the blood buffer system?

• Increases acidity

• Neutralizes excess H⁺

• Releases CO₂

• Decreases pH

If the concentration of H⁺ is 1 × 10⁻⁴ M, what is the pH?

• 5

• 4

• 3

• 2