Acid: Pka:
H20 15.7
NH3 38
HCL -8
NH4+ 9.2
Given the list of pKa values, which acid will have the largest amount of conjugate base present in the solution at equilibrium?
H2O
NH3
NH4+
HCl
I am a little confused by this question. I know that the the smaller the Pka value, the stronger the acid. Since HCL is by far the strongest acid, wouldn't it need more conjugate base than the others to reach equilibrium?
Hey Jameson!
I have the same question. Did you ever figure it out? Also, I'm pretty sure that NH3 isn't the answer. Why do you think HCl isn't the answer?
hey!! Omg I think we are taking the same course. We should totally exchange contact info and help each other out! I also ended up getting NH3 incorrect. I thought HCL would be correct since it was the strongest acid, but upon reading more about the Pka/pH relationship I realized it wouldn't make sense.
To determine which acid will have the largest amount of conjugate base present in the solution at equilibrium, we need to compare the pKa values. The higher the pKa value, the weaker the acid, which means it will have a stronger conjugate base.
Looking at the given pKa values:
- H2O has a pKa of 15.7.
- NH3 has a pKa of 38.
- NH4+ has a pKa of 9.2.
- HCl has a pKa of -8.
Since a higher pKa value indicates a weaker acid, we can see that NH3 has the highest pKa of 38. Therefore, NH3 will have the largest amount of conjugate base present in the solution at equilibrium.