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 liquid junctions, Explain the Liquid junctions? Some galvan...

Explain the Liquid junctions? Some galvanic cells contain two electrolyte solutions with different compositions. These solutions must be separated by a porous barrier or some o

Assignment, The tallest living man today, as recorded, is Allam Chamna of P...

The tallest living man today, as recorded, is Allam Chamna of Pakistan. He is 8 feet and 3 inches tall. What is his height in meter?

Physical properties of acrylic acid, Physical Properties of Acrylic Acid ...

Physical Properties of Acrylic Acid a. Acrylic Acid is colourless pungent smelling liquid. Its boiling point is 141°C. b. Acrylic Acid is miscible with alcohol, water and et

Calculate the temperature of that superheated steam, It is desired to creat...

It is desired to create 5 kg of superheated steam at 300 o C and 20 bar using an isobaric mixer. If 543 kJ of heat are sent to the system, and 2 kg of saturated steam is mixed wit

Alkali metals - non-transition metals, Group 1- Alkali Metals The elemen...

Group 1- Alkali Metals The elements of group 1 are commonly known as alkali metals after the alkaline properties of their hydroxides such as NaOH. The atoms have the (ns) 1 e

Water will not compress, Water will not compress Fit a soda water bottl...

Water will not compress Fit a soda water bottle with a one-hole stopper. By the stopper place the glass tube from a medicine dropper, narrow end up. Fill the bottle to the top

Draw a temperature-composition phase diagram, Q. Use the following informat...

Q. Use the following information to draw a temperature-composition phase diagram for the binary system of H 2 O (A) and Na 2 SO 4 (B) at p = 1 bar, confining t to the range 20 to

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