Acids Flashcards
What is a Bronstead Laury acid?
Proton donor
What is a Bronstead Laury alkali?
Soluble base, OH-
What is Bronstead Laury base?
Proton acceptor
Define a salt
When H+ ions get replaced with metal or ammonium
What salts does sulfuric acid make?
Sulfate 6 salt
Define a monobasic acid
Has 1 H+ ion to dissociate
Eh. HCl
Define a dibasic acid
Has 2 H+ ions to dissociate
Eg. H2SO4
Define a tribasic acid
Has 3 H+ ions to dissociate
Eg. H3PO4
What is the PH equation?
PH=-log [H+]
Define a weak acid
Partially dissociates in water
What is the ka expression?
Ka = [H+][A-] ÷ [HA]
What are the 2 assumptions made when referring to ka?
[HA] doesn’t dissociate
[H+] = [A-]
What does a small pka equal?
Large ka therefore strong acid
What is kW?
Ionisation of water
Pure water is always neutral. What does neutral mean?
Concentration of H+ is equal to Concentration of OH-
Define a buffer
Solution which contains a weak acid and its conjugate bade pair
What happens if you add hydrogen ion to body buffer solution?
[H+] will increase and react with HCO3 to form H2CO3 no change in PH
What happens if you add OH to body buffer solution?
OH will react with H+ to form water the concentration of H+ decreases
H2CO3 + H > HCO3
Maintaining PH
Name some properties of methyl orange
Red to orange at 3.2 to 4.4 PH
Name some properties of phenolphthalein
Colourless to purple at 8.2 to 10.0 PH
What indicator can you use for a strong acid/strong base?
Phenolphthalein and methyl orange
What indicator will you use with a strong acid/weak base?
Methyl orange
What indicator will you use for a weak acid/strong base?
Phenolphthalein
What is the end point of the reaction?
When [HA] turns into A-
What is the equivalence point?
When the colour change occurs
What will happen to an indicator if you add OH- ?
H+ decreases
HA decreases to replace H+
A- will increase and go yellow
What will happen to an indicator if you add H+ ?
H+ will increase
H+ + A- > HA
So HA increases so red appears
