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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 ofH + 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 ofOH 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 asHA, 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, HA(aq) represents an acid molecule dissolved in aqueous solution.H 3 O + (aq) is a notation to indicate that the donated proton has beendissolved in solution. Observations indicate that the proton is associated with several water molecules in a cluster, rather thanattached to a single molecule. H 3 O + is a simplified notation to represent this result. Similarly, theA (aq) ion is solvated by several water molecules. [link] is referred to as acid ionization .

Questions & Answers

what is variations in raman spectra for nanomaterials
Jyoti Reply
I only see partial conversation and what's the question here!
Crow Reply
what about nanotechnology for water purification
RAW Reply
please someone correct me if I'm wrong but I think one can use nanoparticles, specially silver nanoparticles for water treatment.
yes that's correct
I think
what is the stm
Brian Reply
is there industrial application of fullrenes. What is the method to prepare fullrene on large scale.?
industrial application...? mmm I think on the medical side as drug carrier, but you should go deeper on your research, I may be wrong
How we are making nano material?
what is a peer
What is meant by 'nano scale'?
What is STMs full form?
scanning tunneling microscope
how nano science is used for hydrophobicity
Do u think that Graphene and Fullrene fiber can be used to make Air Plane body structure the lightest and strongest. Rafiq
what is differents between GO and RGO?
what is simplest way to understand the applications of nano robots used to detect the cancer affected cell of human body.? How this robot is carried to required site of body cell.? what will be the carrier material and how can be detected that correct delivery of drug is done Rafiq
what is Nano technology ?
Bob Reply
write examples of Nano molecule?
The nanotechnology is as new science, to scale nanometric
nanotechnology is the study, desing, synthesis, manipulation and application of materials and functional systems through control of matter at nanoscale
Is there any normative that regulates the use of silver nanoparticles?
Damian Reply
what king of growth are you checking .?
What fields keep nano created devices from performing or assimulating ? Magnetic fields ? Are do they assimilate ?
Stoney Reply
why we need to study biomolecules, molecular biology in nanotechnology?
Adin Reply
yes I'm doing my masters in nanotechnology, we are being studying all these domains as well..
what school?
biomolecules are e building blocks of every organics and inorganic materials.
anyone know any internet site where one can find nanotechnology papers?
Damian Reply
sciencedirect big data base
Introduction about quantum dots in nanotechnology
Praveena Reply
what does nano mean?
Anassong Reply
nano basically means 10^(-9). nanometer is a unit to measure length.
do you think it's worthwhile in the long term to study the effects and possibilities of nanotechnology on viral treatment?
Damian Reply
absolutely yes
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Source:  OpenStax, Concept development studies in chemistry 2012. OpenStax CNX. Aug 16, 2012 Download for free at http://legacy.cnx.org/content/col11444/1.4
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