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for a concentrated solution of a weak electrolyte a2b3 of concentration c and degree of dissocation a is

User Aarelovich
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Final answer:

In the study of weak electrolytes such as A2B3, one must account for the concentration and degree of dissociation to calculate dissociated ion concentration and pH. Equilibrium concentrations can be derived using an ICE table and the Ka value, while the presence of stronger acids in a mixture can suppress the dissociation of weaker acids.

Step-by-step explanation:

Electrolyte Dissociation and pH Calculation

When discussing a solution of a weak electrolyte, particularly with the given formula A2B3, we need to consider both the concentration (c) of the electrolyte and the degree of dissociation (α). In the context of a weak electrolyte such as A2B3, the concentration of dissociated ions is going to be significantly less than that of strong electrolytes due to the incomplete ionization.

Using a weak acid like acetic acid as an example, the equilibrium concentrations can be calculated with an ICE table and the value of Ka (the acid dissociation constant), which enables the estimation of hydronium ion concentration ([H3O+]) and thus pH. When a weak acid is present with its conjugate base, such as in a buffer solution, the Henderson-Hasselbalch approximation is often used to calculate the pH. However, in a mixture of acids of differing strengths, the stronger acid typically dominates the ionization, thus determining the [H3O+] and suppressing ionization of the weaker acid.

Noting the example provided regarding the conductance characteristic of a 1:1 electrolyte, only options that reflect the properties of weak electrolytes are reasonable. The conductance values suggest that the solution behaves similarly to a 1:1 electrolyte, signifying that its dissociation properties need to be considered accordingly.

User Jkeys
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Final answer:

A concentrated solution of a weak electrolyte A2B3 can be analyzed using the Henderson-Hasselbalch equation and the concept of ionic strength. The concentration of ions A+ and B3- can be calculated based on the concentration of A2B3 and the degree of dissociation.

Step-by-step explanation:

A concentrated solution of a weak electrolyte A2B3 of concentration c and degree of dissociation a can be analyzed using the Henderson-Hasselbalch equation and the concept of ionic strength. The degree of dissociation a represents the fraction of A2B3 that has ionized into ions A+ and B3-. The concentration of ions A+ and B3- can be calculated based on the concentration of A2B3 and the degree of dissociation.

For example, if the concentration of A2B3 is 1M and the degree of dissociation is 0.5, then the concentration of A+ and B3- would be 0.5M each. This is because only half of A2B3 has dissociated into ions.

Therefore, by knowing the concentration of the weak electrolyte and its degree of dissociation, we can determine the concentrations of the individual ions in the solution.

User Winston Kotzan
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