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Feasibility mean rxn hoga ya nahi
hoga. wo T,P,V,H,G per depend karta
hai.
Here we understand
speed of the reaction in everyday
life.
Fast reaction:-This rxn we already done in qualitative analysis practical. For detect of halogen. When we mix AgNO3 quickly white ppt form.
It take million of year for rusting metal.
Slow re
action
In this chapter we study in moderate rate of reaction.
Concentration = n/V
That part is very small so at that when find very small range. We use the method
limit.
Suppose we take glass of
water
But we have two type of
sugar with us.
Catalyst
The law of mass action is a purely
theoretical concept.
Unit of rate constant of
1st order reaction are S-1.
Remember this order is based
on experimental only.
Order base on experimental not based on
reactant concentration.
Molecularity of Reaction
Molecularity based on
theoretical only.
Such type of reaction take
place through a sequence of two
or more consecutive
steps.
Slowest step shows the
overall rate of reaction is called RDS.
Intermediate reaction is formed
in 1 step and consumed in 2nd
step.
Some additional species other then reactant or product is produced in the mechanism called intermediate.
Integrate rate laws
The equation which are obtained by integrating the differential rate laws and which give a direct
relationship between the concentrations of the reactants and times.
Shows the relationship between time and
reactant concentration
A Product
R = -d[A]/dt = k[A]t + 0 Y = m x + c
[A]t = [A]0 e-kt
Y= [A]t X= t
Zero order reaction defined as Reaction whose rate is independent of the reactant concentration and
remains constant throughout the course of the reaction.
x is the amount
consumed in time t.
Rate = -d[A]/dt = k
[A]t
Example of zero order reactions• Decompostion- on Pt surface2NH3(g)
2N2O(g)
PH3 on hot tungston at high pressure unreacted fully.
Pt surrounded by NH3 but only NH3 react with surface of Pt. In this reaction we cant
say rate is depend upon reactant concentration.
Such reaction that have higher order true rate law but are found to behave as first order are called….
Order is an experimentally
determined value.
Every reaction can have only one
particular order.
It happened in those reaction
which contain one solvent.
For finding reaction order we take one
concentration large excess.
Order is high but behaves as 1st order
Apparent order also called fake
order.
This method applicable-
a) Only one reactantA B
b) The order should be integer.
This method applicable-
a) Multiple reactantA + B + C Productb) The order should
be integer.
Svante Arrhenius
Svante August Arrhenius
19 February 1859Wik Castle, Sweden
The reaction rate almost double for every 10
degree rice in temperature.
In this reaction we are using catalyst
Iodine.
2H2O 2H2O + O2
In this reaction we are using catalyst Iodine.
2H2O 2H2O + O2
2KClO3 → 2KCl + 3O2 (Mno2)2H2O2 → 2H2O + O2 (I2)
Catalyst lower the energy barrier.
Svante August Arrhenius
19 February 1859Wik Castle, Sweden
T2 > T1
K2 > K1
Collision Theory And Activation Energy
Effective CollisionRequire Necessary Ea Energy.
GAS PHASE RXN COLLISION IS VERY HIGH STUDY BY
KINETIC MOL THEORY OF GAS
if collision is successful then product formation time is 10-9.
K.E ≥ Ea
THE MINIMUM K.E REQUIRE FOR A MOLECULEAR COLLISION TO LEAD TO REACTION.
3.Orientation of reactant molecule
If orientation is not correct they repelled each other.
Affective collision
when element are arranged in
proper orientation.
Energy of collision comes
from K.E. of colliding
particles.
The minimum energy that molecules need to have in order for a reaction to take place is called the threshold energy.The activation energy is what you need to supply to the
molecules that don't have enough kinetic energy to reach the threshold energy.
All Atom Weakly Link Together.
Potential energy barrier
The fraction of collision that passes the energy f = e –Ea/RT
Collision rate = Z [AC][B]Rate of reaction = P.f x collision rateRate of reaction = P.f.Z[AC][B]Rate of reaction = k [AC][B] where K= P.f.Z
But, f = e –Ea/RT K = P.Z. e –Ea/Rt K = Ae-Ea/RT A= P.Z called frequency factor/ pre-exponent factor.
P is a steric factor that accounts for the need for the molecules to be in the proper orientation.