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

Inorganic salt analysis, analysis of group III basic radicals Ti 4+, Th4+, ...

analysis of group III basic radicals Ti 4+, Th4+, Zr4+, V5+, Ce4+ and UO2 2+

Vsepr :epr principles, Stereochemical arrangement has an issue whenever an ...

Stereochemical arrangement has an issue whenever an atom is bonded to two or more others. Thus triatomic substance AB2 can be bent or linear. It is observed that when a central ato

Explain an lewis acid-base, An Lewis acid-base dissociation of the bromide-...

An Lewis acid-base dissociation of the bromide-essentially an SN1 reaction-gives an a-hydroxy carbo-cation, which is, by resonance, also the conjugate acid of acetophenone. Deproto

Explain the types of isomers, Q. Explain the types of Isomers? Ans. ...

Q. Explain the types of Isomers? Ans. Three types of isomers are chain isomers, position isomers, and functional group isomers: Chain isomers are isomers which differ in

Gas laws, molecular chlorine and molecular fluorine combine to form a gaseo...

molecular chlorine and molecular fluorine combine to form a gaseous product.Under the same conditions of temperature and pressure it is found that one volume of Cl2 reacts with thr

Middle oil of coal tar distillation, Middle oil of coal-tar distillation co...

Middle oil of coal-tar distillation comprise naphthalene and phenolic elements. Phenolic compounds are isolated in subsequent steps. Step a: Middle oil is washed along with H 2

Redox reactions, How do i balance the following equation: Ni+CO==>NI(CO)4? ...

How do i balance the following equation: Ni+CO==>NI(CO)4? I can''t figure out the oxidation state of Ni and C on the product side.

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