, RIHIION
I RATES
Heat of reaction (SH ) -
the net change of chemical potential energy of the system .
Exothermic reaction -
a reaction which transforms chemical potential energy into thermal energy OH <0 exo -
negative
Release heat and thus increase the temperature ol the reaction mixture .
Energy needed to break bonds in the reactants is less than the energy released when the product is formed .
( bond formation )
Potential stored in the bonds of the reactants is greater than the potential energy stored
in the bonds ol the products; products more stable than reactants
energy are
Endothermic reaction -
a reaction which transforms thermal energy into chemical potential energy OH >0 endo -
positive
Absorb heat and thus decreases the temperature ol the reaction mixture .
Energy needed to break bonds in the reactants is more than the energy released when the product is formed . ( bond breaking )
Potential stored in the bonds of the reactants is less than the potential energy stored
in the bonds ol the products; products less stable than reactants
energy are
Activation Energy ( Ea) -
the minimum energ required to start a chemical reaction .
The activated complex is unstable transition state and the
a
high energy ,
, temporary between the reactants products
Energy profile graphs
H =
É products -
Era chants
A Sa
E.A EA
at
SH
Alt
Reaction rate -
the change in concentration per unit time of either a reactant or product Reaction rate & no . effective collisions per unit time .
↳ Effective ( successful ) collision which the have
is one in colliding particles :
the correct orientation
sufficient energy ie .
kinetic energy equal to or
greater than the activation
energy
During the course of a chemical reaction the concentration of reactants decreases and the concentration of products increases
The gradient (slope) of the graph is a measure of the reaction rate .
The steeper the gradient the faster the rate .
The Average reaction rate : the total
change in concentration ( or mass / volume /no .
molest of either products or reactants derided by the time .
↳
Reaction rate is positive for products as they get formed in the reaction
↳
Reaction rate is negative for reactants as they get consumed in the reaction
The rate starts off fast since the number of reactant moles would be high Nellore
,
more effective collisions per unit time leading to the formation ol more product molecules As . the
-
reactants get converted to products the [ reactant ] decreases , therefore less effective collisions per unit time and a slower rate .
I RATES
Heat of reaction (SH ) -
the net change of chemical potential energy of the system .
Exothermic reaction -
a reaction which transforms chemical potential energy into thermal energy OH <0 exo -
negative
Release heat and thus increase the temperature ol the reaction mixture .
Energy needed to break bonds in the reactants is less than the energy released when the product is formed .
( bond formation )
Potential stored in the bonds of the reactants is greater than the potential energy stored
in the bonds ol the products; products more stable than reactants
energy are
Endothermic reaction -
a reaction which transforms thermal energy into chemical potential energy OH >0 endo -
positive
Absorb heat and thus decreases the temperature ol the reaction mixture .
Energy needed to break bonds in the reactants is more than the energy released when the product is formed . ( bond breaking )
Potential stored in the bonds of the reactants is less than the potential energy stored
in the bonds ol the products; products less stable than reactants
energy are
Activation Energy ( Ea) -
the minimum energ required to start a chemical reaction .
The activated complex is unstable transition state and the
a
high energy ,
, temporary between the reactants products
Energy profile graphs
H =
É products -
Era chants
A Sa
E.A EA
at
SH
Alt
Reaction rate -
the change in concentration per unit time of either a reactant or product Reaction rate & no . effective collisions per unit time .
↳ Effective ( successful ) collision which the have
is one in colliding particles :
the correct orientation
sufficient energy ie .
kinetic energy equal to or
greater than the activation
energy
During the course of a chemical reaction the concentration of reactants decreases and the concentration of products increases
The gradient (slope) of the graph is a measure of the reaction rate .
The steeper the gradient the faster the rate .
The Average reaction rate : the total
change in concentration ( or mass / volume /no .
molest of either products or reactants derided by the time .
↳
Reaction rate is positive for products as they get formed in the reaction
↳
Reaction rate is negative for reactants as they get consumed in the reaction
The rate starts off fast since the number of reactant moles would be high Nellore
,
more effective collisions per unit time leading to the formation ol more product molecules As . the
-
reactants get converted to products the [ reactant ] decreases , therefore less effective collisions per unit time and a slower rate .