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

Explain the purposes of tempering, Explain the Purposes of tempering T...

Explain the Purposes of tempering Tempering is a heat treatment approach for alloys and metals. In steels, tempering is done to "toughen" the metal by transforming brittle ma

Calculate the density of ethanol, A 100 gal tank contains 10 lb of water. T...

A 100 gal tank contains 10 lb of water. The tank is filled by two inlet streams, one of pure water and one of pure ethanol. The flow rate of both streams is 10 gal/min. Calculate t

Why there are tie lines for 3 phase equilibrium, Why there are tie lines fo...

Why there are tie lines for 3 phase equilibrium however not for 2-phase equilibrium in a two-component system? Lever rule derived from mass balance gives the relative amounts o

Explain the term acceptance tests, Acceptance tests What are Acceptanc...

Acceptance tests What are Acceptance Tests? Acceptance tests are used to evaluate product acceptability or liking or to determine which of a series of products is the most acc

Titration - volumetric analysis, Titration - Volumetric analysis The pr...

Titration - Volumetric analysis The procedure of addition of the known solution from the burette to the measured volume of solution of the substance to be calculated until the

Dis-advantage of scale and sludge, i need to know the answer for dis-advant...

i need to know the answer for dis-advantage of scale and sludge

Electrochemistry, Explain construction & working of calomel electrode.

Explain construction & working of calomel electrode.

Vapor pressure, Fractional distillation is based on boiling a solution of t...

Fractional distillation is based on boiling a solution of two liquids and collecting the vapor above them multiple times. This method is often used in creating distilled spirits wi

Explain tempering, Tempering is a heat treatment method for metals and all...

Tempering is a heat treatment method for metals and alloys. In steels, tempering is completed to "toughen" the metal by transforming brittle marten site into bainite or a combinat

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