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

Characteristic flame colour - chemical analysis, Characteristic flame colou...

Characteristic flame colour: specific metals and their salts impart particular colours to Bunsen burner flame.         (1)  Pb (plumbum) impart pale greenish colour to the f

Nomenclature of polyfunctional organic compounds, what are polyfunctional c...

what are polyfunctional compounds?expalin the nomenclature of polyfunctional organic compounds with examples

Set of quantum numbers is not possible for 4p electron, Which one of the f...

Which one of the following set of quantum numbers is not possible for 4p  electron : (1) n=4, l=1, m=-1, s= +1/2                 (2) n=4, l=1, m=0, s= +1/2          (3) n=

Difference between oils and fats, Difference between Oils and Fats Oils...

Difference between Oils and Fats Oils and fats belong to similar chemical group, although they are different in their physical state. (i) Oils are liquids at normal temperat

What are metal oxides and oxoanions?, The elements of first transition seri...

The elements of first transition series from variety of oxides of different oxidation states having general formulae  MO, M 2 O 3 , M 3 O 6 , MO 2 , MO 3 . These oxides are gene

What are the values of c and f in systems, Q. What are the values of C and ...

Q. What are the values of C and F in systems consisting of solid AgCl in equilibrium with an aqueous phase containing H 2 O, AgC(aq), Cl(aq), NaC(aq), and NO 3 (aq) prepared in th

Inorganic chemistry, what are binary compounds of hydrogen?describe briefly...

what are binary compounds of hydrogen?describe briefly hydrides formed by alkali metals and halogen?

F-block elements, similarities between the latter actinides and latter lant...

similarities between the latter actinides and latter lanthanides

Explain ratio scales, Ratio scales It is also possible to record likin...

Ratio scales It is also possible to record liking or acceptability using magnitude estimation scaling methods, but consumers may find it difficult to handle the concept of rat

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