2.1 Chemical Equilibrium Flashcards
when is a chemical reaction said to be in equilibrium?
when the composition of the reactants and products remains constant
NOT EQUAL
the effect of a catalyst on equilibrium
speeds up the rate at which equilibrium is reached
no effect on the poe
what is the equilibrium constant?
capital K
what is the concentration of pure solids and liquids in the equilibrium expression?
1
what does the equilibrium constant do?
indicates the position of equilibrium
a small value - towards the left
a large value - towards the right
equilibrium constant units
no units
what is K affected by?
concentration, pressure and catalysts have NO EFFECT
K is dependant upon temperature
what is H30+?
a hydronium ion
a hydrated proton
shorthand expression is H+
what is the ionic product affected by?
temperature
what is the ionic product at 25C?
1 x10^-14
what is the concentration of hydronium and hydroxide ions in a neutral solution? at 25C
10^-7
[H3O+] = [OH-]
pH, conductivity, reaction rate of
strong acid vs weak acid
lower higher
higher lower
higher lower
pH, conductivity, reaction rate of
strong base vs weak base
higher lower
higher lower
higher lower
strong acid + strong base =
neutral solution
weak acid + strong base =
alkaline solution
strong acid + weak base =
acidic solution
how does an acidic buffer solution work?
adding alkali
weak acid hydrogen ions react with OH- which then dissociates replacing the hydrogen ions
adding acid
salt - provides conjugate base which reacts with excess hydrogen ions added
how does a basic buffer solution work?
weka base removes excess H+
conjugate acid from the salt supplies H+ when they are removed
pH range
strong acid strong alkali
3-10
pH range
strong acid weak alkali
3-7
