Which, if any, of the following statements are true? (a) The stronger the base, the smaller the pKb. (b) The stronger the base, the larger the pKb. (c) The stronger the base, the smaller the Kb. (d) The stronger the base, the larger the Kb. (e) The stronger the base, the smaller the pKa of its conjugate acid. (f) The stronger the base, the larger the pKa of its conjugate acid.

Question

Accepted Answer

Hello everyone. So in this video we're trying to identify the incorrect statements so we have statements A through f. We're talking about K. A. And KB values. So the higher the K value, the more acidic it's going to be. And of course that just means it's going to be a weaker base or less acidic. And if we have a smaller K value it's going to be less acidic and more basic. Okay, so one another thing to keep in mind is the PKK and the K values are all going to be in verse. Same thing for this. This is the supplies for our KB values in the P K B values. So the first statement reads the smaller the P K. A. Of its conjugate acid, the weaker the base. So let's go ahead and apply the theory. So we have a smaller P K. A. That just means we have a higher K. A value. If we have very higher K value that we know is acidic or more acidic and it's going to be a weaker base. So A is going to be correct. Okay, so again this is for a let's go ahead and do beat. It reads the smaller the value of its Kb, the weaker the bigs. So we have a small kB value and that just means it's a weaker base. So then B would also be correct. First see it reads the smaller the value of its P K B. Let's go ahead and write that this is going to be foreseen so we have a smaller PKB value. If we have a smaller KB value our key be value then will be increasing because it's an inverse relationship. And that should mean that we have a strong base. But in the statement it reads the weaker the base and that is incorrect. So we have our first incorrect statement here. For C. Next one We have statement D. This one reads. The larger the PK. A. Of its conjugate acid, the stronger the base. So for D we have a bigger P K A. That means we have a smaller K A and we have a smaller K. That's going to be a weak acid. If we have a weak acid, then its conjugate base is going to be a strong base. And the statement then is correct. Okay, next statement we have e. This rates the larger the value of its kB, the weaker the base. So we have a big KB and that should mean that we have a strong base. However, the statement reads that we have a weak base and this is going to be another one of our incorrect statements. Okay, final one. We have a statement F. This one reads a larger the value, it's K B or P K B. So we have a big p k B. This means we have a small KB. And what a small K B value means is that we have a weak base and that's exactly what the statement reads. So this is going to be a correct statement. So statements A through F the only incorrect ones is going to be statement. See, let's highlight that a statement. So statement C and E are going to be our incorrect statement, and that's going to be my final answer for this problem.

Verified Solution

Key Concepts

Base Strength and pKb

Base Strength and Kb

Conjugate Acids and pKa