[aristooo]

i was wondering ... what is the mathematical function for a titration curve of a base being neutralized by an acid ( both being strong bases/acids).

for example this curve :

https://www.google.gr/search?q=titration+of+hcl+naoh&espv=2&biw=1920&bih=979&tbm=isch&imgil=6K00BiWpzoo2iM%253A%253BGsmE3OcIRMA83M%253Bhttp%25253A%25252F%25252Fadsorption.org%25252Fawm%25252Futils%25252FCO2.htm&source=iu&pf=m&fir=6K00BiWpzoo2iM%253A%252CGsmE3OcIRMA83M%252C_&usg=__fXOyhXBxENpePkwyr-5tUNoEUmM%3D&ved=0ahUKEwiZ2prYkeXJAhXK1ywKHZ_LB68QyjcIOQ&ei=gNdzVpmaB8qvswGfl5_4Cg#imgrc=Nj_EeHphKcag4M%3A&usg=__fXOyhXBxENpePkwyr-5tUNoEUmM%3D

[AWK]

Read this discussion
https://www.physicsforums.com/threads/can-titration-curves-be-modeled-with-a-sigmoid-function.157801/

and

http://www.chembuddy.com/?left=pH-calculation&right=titration-curves-calculation

[Arkcon]

Like AWK: posted, the curve shape is called a sigmoidal curve.  Or s-shaped if you must be non-Greek.. You can determine the most inflection points algebraically,if you want to know titration endpoints.  You can model the fiction with a polynomial fit, especially if there's more than one endpoint.

[Borek]

In general: there is no reasonably simple function that you can use.

[aristooo]

Read this discussion
https://www.physicsforums.com/threads/can-titration-curves-be-modeled-with-a-sigmoid-function.157801/

and

http://www.chembuddy.com/?left=pH-calculation&right=titration-curves-calculation

thank you. that was really helpful. i asked this because i was trying to figure out why the ph drops significantly around ph=7 and i thought it might be due to the fact that ph is an exponential climax. meaning that if the (H30+) concentration for example is being reduced by 1000 times the ph increases a lot less.