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

Physical properties of dihydrogen, I want information on physical propertie...

I want information on physical properties of dihydrogen

Determination of acid insoluble ash of flour sample., I want to know how to...

I want to know how to determine the acid insoluble ash of a flour sample with principle,procedure as well as calculations.

Carbon is present as graphite in white cast iron , Cast iron is iron or a f...

Cast iron is iron or a ferrous alloy which has been heated until it liquefies, and is then poured into a mould to solidify. It is usually made from pig iron. The alloy constituents

Explain the geometry of ccl4, Explain the geometry of CCl4 We first hav...

Explain the geometry of CCl4 We first have to know the geometry of CCl4. This should be easy: it's tetrahedral, because the carbon is bonded to four identical groups. Now, as s

Chemical combination, what can be understood from the law of multiple propo...

what can be understood from the law of multiple proportions?

Standard molar reaction enthalpy and temperature dependence, Q: For a homog...

Q: For a homogeneous reaction in which the reactants and products are solutes in a solution, write a rigorous relation between the standard molar reaction enthalpy and the temperat

100, Mixtures can always be separated by physical means. Describe how you w...

Mixtures can always be separated by physical means. Describe how you would separate the components in a mixture of table salt and sand.

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