Question

What does Ka stand for?

Answer 1

`K_a` is the acid dissociation constant, which are extensively tabulated for weak acids.

Explanation:

For an acid, `HA`, in water, we can represent its dissociation in this way:

`HA + H_2O rightleftharpoons H_3O^+ + A^-`

Typically, we can quantify this equilibrium under standard conditions.

`K_a = ([H_3O^+][A^-])/([HA])`

And thus for strong acids, for which the equilibrium lies to the right, we can deduce that `K_a` is large.