Q1 If a weak acid has a low pka valuewhat does that mean In

Q.1) If a weak acid has a low pka value,what does that mean? In general, what can you determine about the pH of that acid?

Q.2) Under what conditions is a drug effective-ionized or un-ionized? Explain your answer.

Q.3) Briefly describe the absorption nmof a drug in the stomach.

I am so confused. Thanks for any help :)

Solution

Q1). The pKa or acid dissociation constant indicates the extent to which the molecule undergo dissociation in the presence of water. Weak acids do not undergo complete dissociation in the presence of water, so their pKa is less. As they release less hydrogen ions, they have higher pH.

Henderson-Hasselbalch equation

pH = pKa + log([A-]/[HA])