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P N O 2 c 2 P N 2 O 4

where c is the slope of the graph. [link] can be rewritten in a standard form

K p P N O 2 2 P N 2 O 4

To test the accuracy of this equation and to find the value of K p , we return to [link] and add another column in which we calculate the value of K p for each of the data points. [link] makes it clear that the "constant" in [link] truly is independent of both the initial conditions and the equilibrium partial pressure of either one of the reactant orproduct. We thus refer to the constant K p in [link] as the reaction equilibrium constant .

Relationship of pressure of product to initial amount of reactant

Equilibrium partial pressures

Equilibrium partial pressures in decomposition reaction
Initial n N 2 O 4 P N 2 O 4 (atm) P N O 2 (atm) K p
0.1 0.00764 0.0336 0.148
0.5 0.0710 0.102 0.148
1 0.166 0.156 0.148
1.5 0.267 0.198 0.148
2 0.371 0.234 0.148
2.5 0.478 0.266 0.148
3 0.586 0.294 0.148
3.5 0.695 0.320 0.148
4 0.805 0.345 0.148
4.5 0.916 0.368 0.148
5 1.027 0.389 0.148

It is very interesting to note the functional form of the equilibrium constant. The productNO 2 pressure appears in the numerator, and the exponent 2 on the pressure is the stoichiometric coefficient onNO 2 in the balanced chemical equation. The reactant N 2 O 4 pressure appears in the denominator, and the exponent 1 on the pressure is the stoichiometric coefficient onN 2 O 4 in the chemical equation.

We now investigate whether other reactions have equilibrium constants and whether the form of this equilibriumconstant is a happy coincidence or a general observation. We return to the reaction for the synthesis of ammonia .

In a previous section , we considered only the equilibrium produced when 1 mole ofN 2 is reacted with 3 moles of O 2 . We now consider a range of possible initial values of theseamounts, with the resultant equilibrium partial pressures given in [link] . In addition, anticipating the possibility of an equilibrium constant, we havecalculated the ratio of partial pressures given by:

K p P N H 3 2 P N 2 P H 2 3

In [link] , the equilibrium partial pressures of the gases are in a very widevariety, including whether the final pressures are greater for reactants or products. However, from the data in [link] , it is clear that, despite these variations, K p in [link] is essentially a constant for all of the initial conditions examined and is thus the reaction equilibrium constant for this reaction .

Equilibrium partial pressures of the synthesis of ammonia
V (L) n N 2 n H 2 P N 2 P H 2 P N H 3 K p
10 1 3 0.0342 0.1027 4.82 6.2 × 10 5
10 0.1 0.3 0.0107 0.0322 0.467 6.0 × 10 5
100 0.1 0.3 0.00323 0.00968 0.0425 6.1 × 10 5
100 3 3 0.492 0.00880 0.483 6.1 × 10 5
100 1 3 0.0107 0.0322 0.467 6.0 × 10 5
1000 1.5 1.5 0.0255 0.00315 0.0223 6.2 × 10 5

Studies of many chemical reactions of gases result in the same observations. Each reaction equilibrium can bedescribed by an equilibrium constant in which the partial pressures of the products, each raised to their corresponding stoichiometriccoefficient, are multiplied together in the numerator, and the partial pressures of the reactants, each raised to theircorresponding stoichiometric coefficient, are multiplied together in the denominator. For historical reasons, this generalobservation is sometimes referred to as the Law of Mass Action .

Questions & Answers

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
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
characteristics of micro business
for teaching engĺish at school how nano technology help us
Do somebody tell me a best nano engineering book for beginners?
s. Reply
there is no specific books for beginners but there is book called principle of nanotechnology
what is fullerene does it is used to make bukky balls
Devang Reply
are you nano engineer ?
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.
what is the actual application of fullerenes nowadays?
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.
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?
carbon nanotubes has various application in fuel cells membrane, current research on cancer drug,and in electronics MEMS and NEMS etc
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
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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, 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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