Which of the following mixtures has the higher pH?
(a) Equal volumes of 0.10 M HCN and 0.10 M NaOH
(b) Equal volumes of 0.10 M HClO4 and 0.10 M NaOH

Question

Which of the following mixtures has the higher pH? 
(a) Equal volumes of 0.10 M HCN and 0.10 M NaOH 
(b) Equal volumes of 0.10 M HClO4 and 0.10 M NaOH

Accepted Answer

Hello everyone today. We are the fallen question, identify the acid based mixture with the greatest with the greater ph value. So we have A and we have B. So first let's work with a So with a the reaction is as follows, we have acetic acid here and it's reacting with a strong base or sodium hydroxide and it's going to form us our acetate ion however, with a sodium ion present on it as well as water. So it was noted that there was equal volumes and if you look at here at their polarities, they are also equal. We can say that the number of moles of acid and base are equal. So we're essentially at the equivalence point where all of the asset has reacted with all of the base. And so in this case our mixture will only contain these acetate ions. And so this acetate is going to be the conjugate base of this acetic acid, which is a weak acid and conjugate bases of weak assets are basic in nature. So that would therefore make this solution basic at equilibrium. If we move on to be, the reaction is going to be our hydra bronek acid reacting with a strong base. This is essentially a strong a strong acid and a strong base. This is going to give us our potassium bromide as well as our water ions. So once again our polarities are equal and our volumes are equal, the number of moles are equal to the number of acid are equal to the number of moles of base. So we're at the equivalence point and in this case we're only going to have a solution that contains potassium and bromide islands. So if we break up potassium bromine, we're gonna get potassium ions and bromine ions. Now potassium is a group one a element and group one elements are neutral bromide, however, is the conjugate base of this strong acid, which was this hydroponic acid. And so conjugate bases of strong acids are also neutral. So what determines what if something is acidic or basic? Well, if we look at the ph, the ph can be three different things. It can be greater than it can be less than seven equal to seven or greater than seven. If it is less than seven, we have an acidic solution. If it is equal to seven, it is neutral. And if it is greater than seven it is basic. Since solution a is basic, it is going to have the higher ph So therefore the answer that will have the highest ph will be answered twice. A and with that we have answered the question overall, I hope this helped. And until next time

Which of the following mixtures has the higher pH? (a) Equal volumes of 0.10 M HCN and 0.10 M NaOH (b) Equal volumes of 0.10 M HClO4 and 0.10 M NaOH

Verified Solution

Key Concepts

Acid-Base Reactions

pH Scale

Neutralization