Summary Chemical equilibrium notes

-
Chemical_ Equilibriar -




Open System :
System in which both
energy
and matter can be
exchanged between the system and




it's
surroundings
Cannot reach equilibrium



Closed System System in which mass is conserved but can enter leave
energy or
:




Can reach equilibrium




Reversible -
Reaction-




Products
·


can be converted back into reactants


for forward
Enthalpy change reaction
*
is
ex o


3Ha + Na 2NH3 Ho
- -
endo




-Chemical Equilibrium - -




Forward
·



and reverse reactions are at the same rate


Concentration of
-




products and reactants is equal



&



-------- Na &




---
==
&
N --- Ha


o
-------




"
- - - -




NHy
- - -

-
1- -
-




!
-



-
-
-
- -

time(s) time(s)

, _
Le _
ChateliersPrinciple-




When an external stress is applied to a
system in dynamic chemical equilibrium ,
the



equilibrium point will
change in such
ray
a as to counteract the stress




Describing a shift in chemical equilibrium :




1 the
.


Identify external stress

I
------------------
Pressure
I Catalysts increases forward and reverse
I

I

I
-




Temperature !
reactions :No infact on equilibrium
I

L


Concentration




2 State the
.

systems response



System will respond to counteract stress




.
3 State which reaction is favored and equilibrium shift




Pressure-

· Favours forward reaction
Less moles produced
·


If
----------
pressure increases -




*
exo
-Volume is decreased 3Ha + Na 2NHa Ho
endo

*
System favors reaction with fewer
-



moles
-
This
-
decreases Pressure
-

"Favours
decreased--------
reverse reaction


·

If pressure is More moles produced


Volume of container increases



System favors that
-




reaction produces more molecules



This the pressure
-




increases