Which of the following mixtures will result in the formation of a buffer solution when dissolved in 1.00 L of water?
i) 0.50 mol HClO2 and 0.25 mol HCl.
ii) 0.50 mol HClO2 and 0.25 mol NaOH.
iii) 0.50 mol NaClO2 and 0.50 mol HClO2.
iv) 0.50 mol NaClO2 and 0.50 mol HCl.
Buffers are composed of a weak acid and its salt OR a weak base and its salt.
ii will do it. NaOH reacts with HClO2 to form NaClO2 and there is some HClO2 un-reacted. That makes a weak acid and its salt. iii is a salt and the weak acid.
Thanks a lot!
To determine which of the mixtures will result in the formation of a buffer solution, we need to understand what a buffer solution is.
A buffer solution is a solution that can resist changes in pH when a small amount of acid or base is added to it. It consists of a weak acid and its conjugate base or a weak base and its conjugate acid. Buffers are important in maintaining the pH of biological systems, as they can stabilize the pH by absorbing or releasing H+ ions.
To identify a buffer solution, we need to check if the mixture contains both a weak acid and its conjugate base or a weak base and its conjugate acid.
Let's analyze each of the given mixtures:
i) 0.50 mol HClO2 and 0.25 mol HCl
In this mixture, we have HClO2, which is a weak acid, and HCl, which is a strong acid. Since HCl is not a conjugate base of HClO2, this mixture does not contain a weak acid and its conjugate base. Therefore, it will not form a buffer solution.
ii) 0.50 mol HClO2 and 0.25 mol NaOH
In this mixture, we have HClO2, which is a weak acid, and NaOH, which is a strong base. Since NaOH is not a conjugate acid of HClO2, this mixture does not contain a weak acid and its conjugate base. Therefore, it will not form a buffer solution.
iii) 0.50 mol NaClO2 and 0.50 mol HClO2
In this mixture, we have NaClO2, which is a salt derived from a weak acid (HClO2), and HClO2 itself. Since NaClO2 is the conjugate base of HClO2, this mixture contains a weak acid (HClO2) and its conjugate base (NaClO2). Therefore, it will form a buffer solution.
iv) 0.50 mol NaClO2 and 0.50 mol HCl
In this mixture, we have NaClO2, which is a salt derived from a weak acid (HClO2), and HCl, which is a strong acid. Since HCl is not a conjugate base of HClO2, this mixture does not contain a weak acid and its conjugate base. Therefore, it will not form a buffer solution.
Therefore, the mixture that will result in the formation of a buffer solution is iii) 0.50 mol NaClO2 and 0.50 mol HClO2.