00:01
All right, so we're told to calculate the acid dissociation constant, right? and we're given the concentrations of the species, right? so what we have here is the ha plus water, giving us the hydronium ion and the conjugate base.
00:31
And we're told that the ph of the solution was 1 .542.
00:36
And we're told that from part a, the concentration of species in solution is, we're given the concentrations of the species, right? we're told that this was 0 .02871, that's the conjugate base, 0 .02871.
00:53
And we're told that the acid itself was 0 .2086, right? and we're given the ph of the solution.
01:10
So quite clearly, we can tell that first, the ka expression, let me see, let me just write that the acid dissociation expression of this, the acid dissociation expression is where i should start from, the ka.
01:26
The ka would be, is given as the concentration of hydronium ion, as it could be, multiplied by the concentration of the conjugate base divided by the concentration of the acid, right? at equilibrium.
01:44
Now, so what we have been provided with are the concentrations at equilibrium.
01:52
That's what we have been given.
01:54
The concentrations at equilibrium is what we have been provided with, right? so we're just going to substitute those values.
02:00
And i should say that we already determined the concentration of the hydronium ion, which is equal to the concentration of the conjugate base, the a minus...