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We have developed an understanding of equilibrium involving phase transitions and involving reactions entirely in the gas phase. We will assume anunderstanding of the principles of dynamic equilibrium, reaction equilibrium constants, and Le Châtelier's Principle . To understand application of these principles to reactions in solution, we willnow assume a definition of certain classes of substances as being either acids or bases. An acid is a substance whose moleculesdonate positive hydrogen ions (protons) to other molecules or ions. When dissolved in pure water, acid molecules will transfer ahydrogen ion to a water molecule or to a cluster of several water molecules. This increases the concentration of H + ions in the solution. A base is a substance whose molecules accept hydrogen ions from other molecules. When dissolved in pure water,base molecules will accept a hydrogen ion from a water molecule, leaving behind an increased concentration of O H - ions in the solution. To understand what determines acid-base behavior, we will assume an understanding of the bonding,structure, and properties of individual molecules.


Acids and bases are very common substances whose properties vary greatly. Many acids are known to be quitecorrosive, with the ability to dissolve solid metals or burn flesh. Many other acids, however, are not only benign but vital to theprocesses of life. Far from destroying biological molecules, they carry out reactions critical for organisms. Similarly, many basesare caustic cleansers while many others are medications to calm indigestion pains.

In this concept study, we will develop an understanding of the characteristics of molecules which make themeither acids or bases. We will examine measurements about the relative strengths of acids and bases, and we will use these todevelop a quantitative understanding of the relative strengths of acids and bases. From this, we can develop a qualitativeunderstanding of the properties of molecules which determine whether a molecule is a strong acid or a weak acid, a strong baseor a weak base. This understanding is valuable in predicting the outcomes of reactions, based on the relative quantitative strengthsof acids and bases. These reactions are commonly referred to as neutralization reactions. A surprisingly large number of reactions,particularly in organic chemistry, can be understood as transfer of hydrogen ions from acid molecules to base molecules.

Observation 1: strong acids and weak acids

From the definition of an acid given in the Foundation, a typical acid can be written as H A , representing the hydrogen ion which will be donated and the rest ofthe molecule which will remain as a negative ion after the donation. The typical reaction of an acid in aqueous solutionreacting with water can be written as

H A ( aq ) + H 2 O ( l ) H 3 O + ( aq ) + A - ( aq )

In this reaction, H A ( aq ) represents an acid molecule dissolved in aqueous solution. H 3 O + ( aq ) is a notation to indicate that the donated proton has been dissolved in solution. Observations indicate that the proton isassociated with several water molecules in a cluster, rather than attached to a single molecule. H 3 O + is a simplified notation to represent this result. Similarly, the A - ( aq ) ion is solvated by several water molecules. [link] is referred to as acid ionization .

Questions & Answers

how to know photocatalytic properties of tio2 nanoparticles...what to do now
Akash Reply
it is a goid question and i want to know the answer as well
Do somebody tell me a best nano engineering book for beginners?
s. Reply
what is fullerene does it is used to make bukky balls
Devang Reply
are you nano engineer ?
what is the Synthesis, properties,and applications of carbon nano chemistry
Abhijith Reply
Mostly, they use nano carbon for electronics and for materials to be strengthened.
is Bucky paper clear?
so some one know about replacing silicon atom with phosphorous in semiconductors device?
s. Reply
Yeah, it is a pain to say the least. You basically have to heat the substarte up to around 1000 degrees celcius then pass phosphene gas over top of it, which is explosive and toxic by the way, under very low pressure.
Do you know which machine is used to that process?
how to fabricate graphene ink ?
for screen printed electrodes ?
What is lattice structure?
s. Reply
of graphene you mean?
or in general
in general
Graphene has a hexagonal structure
On having this app for quite a bit time, Haven't realised there's a chat room in it.
what is biological synthesis of nanoparticles
Sanket Reply
what's the easiest and fastest way to the synthesize AgNP?
Damian Reply
types of nano material
abeetha Reply
I start with an easy one. carbon nanotubes woven into a long filament like a string
many many of nanotubes
what is the k.e before it land
what is the function of carbon nanotubes?
I'm interested in nanotube
what is nanomaterials​ and their applications of sensors.
Ramkumar Reply
what is nano technology
Sravani Reply
what is system testing?
preparation of nanomaterial
Victor Reply
Yes, Nanotechnology has a very fast field of applications and their is always something new to do with it...
Himanshu Reply
good afternoon madam
what is system testing
what is the application of nanotechnology?
In this morden time nanotechnology used in many field . 1-Electronics-manufacturad IC ,RAM,MRAM,solar panel etc 2-Helth and Medical-Nanomedicine,Drug Dilivery for cancer treatment etc 3- Atomobile -MEMS, Coating on car etc. and may other field for details you can check at Google
anybody can imagine what will be happen after 100 years from now in nano tech world
after 100 year this will be not nanotechnology maybe this technology name will be change . maybe aftet 100 year . we work on electron lable practically about its properties and behaviour by the different instruments
name doesn't matter , whatever it will be change... I'm taking about effect on circumstances of the microscopic world
how hard could it be to apply nanotechnology against viral infections such HIV or Ebola?
silver nanoparticles could handle the job?
not now but maybe in future only AgNP maybe any other nanomaterials
I'm interested in Nanotube
this technology will not going on for the long time , so I'm thinking about femtotechnology 10^-15
can nanotechnology change the direction of the face of the world
Prasenjit Reply
how did you get the value of 2000N.What calculations are needed to arrive at it
Smarajit Reply
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Source:  OpenStax, General chemistry ii. OpenStax CNX. Mar 25, 2005 Download for free at http://cnx.org/content/col10262/1.2
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