DAT - Dental Admission General Chemistry: Acid-Base Chemistry Flashcards
6 cards from real DAT practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 6 DAT - Dental Admission General Chemistry: Acid-Base Chemistry flashcards as text
A buffer solution resists pH changes upon addition of small amounts of:
Answer: Strong acid or strong base
A buffer resists pH changes when small amounts of strong acid or strong base are added by neutralizing them through its weak acid/conjugate base equilibrium.
The Henderson-Hasselbalch equation for a buffer is: pH =
Answer: pKa + log([A⁻]/[HA])
The Henderson-Hasselbalch equation pH = pKa + log([A⁻]/[HA]) relates buffer pH to the pKa and ratio of conjugate base to weak acid.
Which combination forms an effective buffer?
Answer: CH₃COOH and CH₃COONa
An effective buffer requires a weak acid and its conjugate base, such as acetic acid (CH₃COOH) and sodium acetate (CH₃COONa).
The bicarbonate buffer system in blood maintains physiological pH at approximately:
Answer: 7.4
The H₂CO₃/HCO₃⁻ buffer system is the primary blood buffer, maintaining pH at approximately 7.4 (normal range 7.35–7.45).
A buffer is most effective when the solution pH is close to:
Answer: The pKa of the weak acid component
A buffer provides maximum buffering capacity when pH is within ±1 unit of the weak acid's pKa.
What happens to pH when the buffer capacity is exceeded by addition of a large amount of strong base?
Answer: pH increases dramatically once the buffer capacity is exhausted
Once all the weak acid component is consumed, additional strong base causes a sharp, dramatic increase in pH.