Question

Assume that five weak acids, identified only by numbers (1, 2, 3, 4, and 5) have the following ionization constants:

A₁ - Kₐ = 1.0 x 10⁻³
A₂ - Kₐ = 3.0 x 10⁻⁵
A₃ - Kₐ = 2.6 x 10⁻⁷
A₄ - Kₐ = 4.0 x 10⁻⁹
A₅ - Kₐ = 7.3 x 10⁻¹¹
The anion of which acid is the strongest base?

Answer 1

The anion of acid A5, which has the smallest acid-ionization constant (Ka = 7.3 x 10^-11), is the strongest base.

Step-by-step explanation:

The anion of the acid with the smallest acid-ionization constant (Ka) would be the strongest base. This is because there is an inverse relationship between the strength of an acid and its conjugate base: the weaker the acid, the stronger its conjugate base.

From the given weak acids with ionization constants:

1. A1 - Ka = 1.0 x 10-3
2. A2 - Ka = 3.0 x 10-5
3. A3 - Ka = 2.6 x 10-7
4. A4 - Ka = 4.0 x 10-9
5. A5 - Ka = 7.3 x 10-11

The anion of acid A5 is the strongest base because it has the smallest Ka value.