# 0.18 Reaction equilibrium in the gas phase  (Page 4/6)

 Page 4 / 6
${P}_{\text{N}{\text{O}}_{2}}=c\sqrt{{P}_{{\text{N}}_{2}{\text{O}}_{4}}}$

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

${K}_{p}=\frac{{P}_{\text{N}{\text{O}}_{2}}^{2}}{{P}_{{\text{N}}_{2}{\text{O}}_{4}}}$

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 .

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:

${K}_{p}=\frac{{P}_{\text{N}{\text{H}}_{3}}^{2}}{{P}_{{\text{N}}_{2}}{P}_{{\text{H}}_{2}}^{3}}$

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) ${n}_{{\text{N}}_{2}}$ ${n}_{{\text{H}}_{2}}$ ${P}_{{\text{N}}_{2}}$ ${P}_{{\text{H}}_{2}}$ ${P}_{\text{N}{\text{H}}_{3}}$ ${K}_{p}$
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 .

what is the stm
is there industrial application of fullrenes. What is the method to prepare fullrene on large scale.?
Rafiq
industrial application...? mmm I think on the medical side as drug carrier, but you should go deeper on your research, I may be wrong
Damian
How we are making nano material?
what is a peer
What is meant by 'nano scale'?
What is STMs full form?
LITNING
scanning tunneling microscope
Sahil
how nano science is used for hydrophobicity
Santosh
Do u think that Graphene and Fullrene fiber can be used to make Air Plane body structure the lightest and strongest. Rafiq
Rafiq
what is differents between GO and RGO?
Mahi
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
Rafiq
what is Nano technology ?
write examples of Nano molecule?
Bob
The nanotechnology is as new science, to scale nanometric
brayan
nanotechnology is the study, desing, synthesis, manipulation and application of materials and functional systems through control of matter at nanoscale
Damian
Is there any normative that regulates the use of silver nanoparticles?
what king of growth are you checking .?
Renato
What fields keep nano created devices from performing or assimulating ? Magnetic fields ? Are do they assimilate ?
why we need to study biomolecules, molecular biology in nanotechnology?
?
Kyle
yes I'm doing my masters in nanotechnology, we are being studying all these domains as well..
why?
what school?
Kyle
biomolecules are e building blocks of every organics and inorganic materials.
Joe
anyone know any internet site where one can find nanotechnology papers?
research.net
kanaga
sciencedirect big data base
Ernesto
Introduction about quantum dots in nanotechnology
what does nano mean?
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?
absolutely yes
Daniel
how to know photocatalytic properties of tio2 nanoparticles...what to do now
it is a goid question and i want to know the answer as well
Maciej
Abigail
for teaching engĺish at school how nano technology help us
Anassong
How can I make nanorobot?
Lily
Do somebody tell me a best nano engineering book for beginners?
there is no specific books for beginners but there is book called principle of nanotechnology
NANO
how can I make nanorobot?
Lily
what is fullerene does it is used to make bukky balls
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
Got questions? Join the online conversation and get instant answers! By     By    