Bipolarity

I made up this limit problems trying to understand something in chemistry, so they may not necessarily have any answer.

I am not sure how to evaluate them analytically. Not sure how L'Hopital's Rule would work here either.

[tex] (\lim_{V→50^{-}}-log(\frac{50-V}{10(V+50)})) [/tex]

[tex] 14+(\lim_{V→50^{+}}log(\frac{V-50}{10(V+50)})) [/tex]

[tex] 14+(\lim_{V→∞}log(\frac{V-50}{10(V+50)})) [/tex]

I would greatly appreciate all your help on these questions!

Just in case anyone asks, I am trying to model the pH of a solution as a function of the volume of titrant added, but I want to make sure it is piece-wise continuous.

Thanks!

BiP