Ph scale, Chemistry

Assignment Help:

Being simultaneously basic and acidic, water undergoes autoprotolysis, also called self-ionization:

1192_Untitled.png

The equilibrium constant is

1847_Untitled.png

 

H3O+ in these equations is general simply written H+. In pure water and in solutions that do not give any additional source of H+ or OH- both ions have molar concentrations exact to 10-7. Addition of an acid decreases [OH-] and hence increases [H3O+]; addition of a base has the reverse effect.

 

The pH scale is defined by

 

450_Untitled.png

Neutral water has a pH of 7, acidic solutions have lower values of ph (typically 0-7), and basic solutions or alkaline higher values (7-14). In alkaline or basic solutions [OH-] is thus greater than [H+].

 

Strong and weak behavior

The equilibrium constant of the protolysis reaction

 

451_Untitled.png

is known as the acid dissociation constant (Ka) of HA or the acidity constant:

 

219_Untitled.png

It is often expressed as a pKa value, described as

 

80_Untitled.png


Related Discussions:- Ph scale

classification of polymers - semi synthetic polymers, Semi-synthetic polym...

Semi-synthetic polymers Rayon and other cellulose derivatives such as cellulose nitrate, cellulose acetate so on, are semi-synthetic polymers. These illustrated as thermoplasti

Illustrate the structure of alkanes, Q. Illustrate the structure of Alkanes...

Q. Illustrate the structure of Alkanes? Ans. Alkanes have the general formula C n H 2n+2 . This means that for every n atoms of carbon, there are 2n + 2 atoms of hydrogen.

Uses of sucrose, Uses of Sucrose, Cane-sugar (1) Sucrose is used as a s...

Uses of Sucrose, Cane-sugar (1) Sucrose is used as a sweetening substance for several jams, syrups sweets, food preparations etc. (2) Sucrose is used in the making of sucros

Electronic configuration of sc21 is, Electronic configuration of Sc 21   is...

Electronic configuration of Sc 21   is: (1) 1s 2 , 2s 2 , 2p 6 , 3s 2 , 3p 6 , 4s 2 , 3d 1               (2) 1s 2 , 2s 2 , 2p 6 , 3s 2 , 3p 6 , 4s 1 , 3d 2           (3)1

Coulumerty, what are the applications of coulumetry ?

what are the applications of coulumetry ?

The wall thickness can be minimized by insulation layer, The wall thickness...

The wall thickness can be minimized by insulation layer The wall thickness can be minimized by insulation layers. A typical wall having of a brick layer that has a thickness of

Allow the hydrogen atom , Which electronic level would allow the hydrogen a...

Which electronic level would allow the hydrogen atom to absorb a photon but not to emit a photon Ans) We know the energy of electron goes on to become more negative as it reache

What is the methyle orange formula?, Methyl orange is a pH indicator often ...

Methyl orange is a pH indicator often used in titrations. It''s chemical formula  is C 14 H 14 N 3 NaO 3 S

Write Your Message!

Captcha
Free Assignment Quote

Assured A++ Grade

Get guaranteed satisfaction & time on delivery in every assignment order you paid with us! We ensure premium quality solution document along with free turntin report!

All rights reserved! Copyrights ©2019-2020 ExpertsMind IT Educational Pvt Ltd