Question

If and acid has a Ka dissociation constant of 1 x 10-9 what is the pKa of this acid?

Answer 1

pKa = 9

Step-by-step explanation:

In this case, we have to remember the meaning of "p". When we use "p" in any calculation we have to apply the minus ten based logarithm, so:

`p~=~-Log`

For example, when we use the "pH" value. We have to apply the minus ten based logarithm of the concentration of the hydronium ion:

`pH~=~-Log[H^+]`

So, if we have wanted to calculate the pKa value. We have to apply the minus ten based logarithm of the Ka value, so:

`pKa~=~-Log~Ka`

Now we can plug the value into the equation:

`pKa~=~-Log~1x10^-^9`

`pKa~=~9`

The pKa value is 9.

I hope it helps!