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Electrolytes, ionisation and conductivity

Conductivity in aqueous solutions, is a measure of the ability of water to conduct an electric current. The more ions there are in the solution, the higher its conductivity.

Conductivity
Conductivity is a measure of a solution's ability to conduct an electric current.

Electrolytes

An electrolyte is a material that increases the conductivity of water when dissolved in it. Electrolytes can be further divided into strong electrolytes and weak electrolytes .

Electrolyte
An electrolyte is a substance that contains free ions and behaves as an electrically conductive medium. Because they generally consist of ions in solution, electrolytes are also known as ionic solutions.
  1. Strong electrolytes A strong electrolyte is a material that ionises completely when it is dissolved in water:
    AB (s, l, g) A + (aq) + B - (aq)
    This is a chemical change because the original compound has been split into its component ions and bonds have been broken. In a strong electrolyte, we say that the extent of ionisation is high. In other words, the original material dissociates completely so that there is a high concentration of ions in the solution. An example is a solution of potassium nitrate:
    KNO 3 (s) K + (aq) + NO 3 - (aq)
  2. Weak electrolytes A weak electrolyte is a material that goes into solution and will be surrounded by water molecules when it is added to water. However, not all of the molecules will dissociate into ions. The extent of ionisation of a weak electrolyte is low and therefore the concentration of ions in the solution is also low.
    A B ( s , l , g ) A B ( a q ) A + ( aq ) + B - ( aq )
    The following example shows that in the final solution of a weak electrolyte, some of the original compound plus some dissolved ions are present.
    C 2 H 3 O 2 H ( l ) C 2 H 3 O 2 H C 2 H 3 O 2 - ( aq ) + H + ( aq )

Non-electrolytes

A non-electrolyte is a material that does not increase the conductivity of water when dissolved in it. The substance goes into solution and becomes surrounded by water molecules, so that the molecules of the chemical become separated from each other. However, although the substance does dissolve, it is not changed in any way and no chemical bonds are broken. The change is a physical change . In the oxygen example below, the reaction is shown to be reversible because oxygen is only partially soluble in water and comes out of solution very easily.

C 2 H 5 OH ( l ) C 2 H 5 OH ( aq )
O 2 ( g ) O 2 ( aq )

Factors that affect the conductivity of water

The conductivity of water is therefore affected by the following factors:

  • The type of substance that dissolves in water. Whether a material is a strong electrolyte (e.g. potassium nitrate, KNO 3 ), a weak electrolyte (e.g. acetate, CH 3 COOH ) or a non-electrolyte (e.g. sugar, alcohol, oil) will affect the conductivity of water because the concentration of ions in solution will be different in each case.
  • The concentration of ions in solution. The higher the concentration of ions in solution, the higher its conductivity will be.
  • Temperature. The warmer the solution, the higher the solubility of the material being dissolved and therefore the higher the conductivity as well.

Questions & Answers

what does nano mean?
Anassong Reply
nano basically means 10^(-9). nanometer is a unit to measure length.
Bharti
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
Daniel
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
Maciej
characteristics of micro business
Abigail
for teaching engĺish at school how nano technology help us
Anassong
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 ?
s.
fullerene is a bucky ball aka Carbon 60 molecule. It was name by the architect Fuller. He design the geodesic dome. it resembles a soccer ball.
Tarell
what is the actual application of fullerenes nowadays?
Damian
That is a great question Damian. best way to answer that question is to Google it. there are hundreds of applications for buck minister fullerenes, from medical to aerospace. you can also find plenty of research papers that will give you great detail on the potential applications of fullerenes.
Tarell
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.
Virgil
is Bucky paper clear?
CYNTHIA
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.
Harper
Do you know which machine is used to that process?
s.
how to fabricate graphene ink ?
SUYASH Reply
for screen printed electrodes ?
SUYASH
What is lattice structure?
s. Reply
of graphene you mean?
Ebrahim
or in general
Ebrahim
in general
s.
Graphene has a hexagonal structure
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On having this app for quite a bit time, Haven't realised there's a chat room in it.
Cied
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Sanket Reply
what's the easiest and fastest way to the synthesize AgNP?
Damian Reply
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Cied
types of nano material
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I start with an easy one. carbon nanotubes woven into a long filament like a string
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what is the function of carbon nanotubes?
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what is nanomaterials​ and their applications of sensors.
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what is system testing?
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preparation of nanomaterial
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how to synthesize TiO2 nanoparticles by chemical methods
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how did you get the value of 2000N.What calculations are needed to arrive at it
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Source:  OpenStax, Siyavula textbooks: grade 10 physical science [caps]. OpenStax CNX. Sep 30, 2011 Download for free at http://cnx.org/content/col11305/1.7
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