Acid Base Equilibria Flashcards
What’s a Brønsted-Lowry acid?
A proton donator
What’s a Brønsted-Lowry base?
A proton acceptor
What’s the definition for a strong acid?
An acid that completely dissociates to ions when in a solution with a pH of 0-1
Define a weak acid.
An acid that only slightly dissociates in a solution with pH 3-7
Why does an equilibrium form when reacting weak acids/bases?
They only slightly dissociate
What’s the equation for determining pH of a strong acid/base?
pH = -log10[H+]
What’s the equation for weak acid?
Ka = [H+][A-] / [HA]
What’s the equation for the ionic product of water?
Kw = [H+][OH-]
Is the reversible reaction of H2O to its ions endo or exo
H2O ⇌ H+ + OH-
The forward reaction is endothermic, so when temperature increases system shifts to the right, therefore becomes more acidic.
What’s the neutralisation point of a titration curve?
A large verticals section of the graph
How do you make a titration curve more accurate?
Add smaller volume of acids and bases
Where does the neutralisation point occur for each combination of strong/weak acid/base?
Strong acid + strong base = 7
Strong acid + weak base <7
Weak acid + Strong base > 7
Weak acid + Weak base = N/A
At the equivalence point thr pH is equal to pKa (True/False)
False, occurs at half equivalence point
How is a buffer formed?
A weak acid and its salt
Or a weak acid and a base
Why do buffers resist any change in pH?
A mixture of H+ ions and a large reservoir of OH- ions are produced
What is a buffer solution?
A solution which is able to resist changes in pH when small volumes of acid or base are added
What’s a Homogenous equilibrium
Reactions in which the reactants and products are in the same phase/state
What’s the equation for partial pressure
(Moles of X / Total moles) * Total Pressure
Does concentration/pressure affect Kc or amp
No it doesn’t
What’s the effect of using a catalyst on Kc and Kp
No effect
What are two assumptions when using Ka?
No H+ ions arrive from thr ionisation of water.
No H+ ions arrive from the dissociation of the weak acid. Initial = equlibrium
What does amphoteric mean?
A substance that reacts with both acids and bases (accepts or donates electrons)
