lecture 10 - acids and bases Flashcards
What is an amphiprotic substance?
A substance that can act as both an acid and a base (e.g., water).
What is the difference between H⁺ and H₃O⁺?
H⁺ is a proton, while H₃O⁺ is the hydrated form of H⁺ in water.
Q: What happens to an acid in a Brønsted-Lowry reaction?
A: It donates a proton to form its conjugate base.
What is the key difference between strong and weak acids?
A: Strong acids completely dissociate in water; weak acids only partially dissociate.
Q: How does the strength of a base relate to the strength of its conjugate acid?
A: A stronger base has a weaker conjugate acid.
• Q: What do the arrows in acid-base reactions represent?
A: Single arrow for complete dissociation (strong acids); double arrow for equilibrium (weak acids).
Q: What is Ka?
A: The acid dissociation constant, representing the strength of an acid.
Q: What happens to the pH if [H⁺] increases?
A: The pH decreases, indicating increased acidity.
Q: What are the components of a buffer?
A: A weak acid and its conjugate base, or a weak base and its conjugate acid.
Q: How does a buffer maintain pH?
A: By neutralizing added acids or bases.
Q: What is the Henderson-Hasselbalch equation used for?
A: To calculate the pH of a buffer.
Q: Why do strong acids not require Ka values for calculations?
A: Because they completely dissociate, making equilibrium considerations unnecessary.
Q: What does it mean if a substance has negligible acidity?
A: It does not exhibit acidic behavior in water, and its conjugate base is extremely strong.
