Acids, Bases & pH Flashcards
State the Brønsted-Lowry definition of an acid:
Acids are proton doners.
State the Brønsted-Lowry definition of an base:
Bases are proton acceptors
State what a strong base means and give an example.
Strong bases ionise almost completely in water.
NaOH
Reaction:
NaOH —> Na+ + OH-
State what a strong acid means and give an example.
A strong acid dissociates almost completely in water.
HCl
Reaction:
HCl —> H+ + Cl-
State what a weak base means and give an example.
A week base only slightly ionises in water.
NH3
Reaction:
NH3 + H2O NH4+ + OH-
State what a weak acid means and give an example.
A weak acid dissociates very slightly in water.
CH3COOH
Reaction:
CH3COOH CH3COO- + H+
State the expression for the ionic product of water and give its units.
Kw = [H+][OH-]
mol2 dm-6
Definition of a monoprotic acid:
[H+] = [Acid]
Definition of a diprotic acid:
[H+] = 2[Acid]
What is Ka?
The acid dissociation constant.
It applies to an acid at a specific temperature regardless of concentration.
What indicator should you use in a strong acid/strong base reaction?
Methyl orange
Phenolphthalein
What indicator should you use in a strong acid/weak base reaction?
Methyl orange
What indicator should you use in a weak acid/strong base reaction?
Phenolphthalein
What indicator should you use in a weak acid/weak base reaction?
pH meter
What colour is methyl orange at a low pH?
Red
