Acids and Bases Flashcards
What is Kw?
The ionic product of water
What is the pH scale a measure of?
Hydrogen ion conc.
Define a Bronsted-Lowry acid
A proton donor - they release H+ ions when they are mixed with water
Define a Bronsted-Lowry base
Proton acceptors
What are the three types of acid?
Monobasic, dibasic, tribasic
What is a conjugate pair?
Acids and bases that are linked by the transfer of a proton
What are the products of acid + metal?
Salt + Hydrogen
What are the products of acid + carbonate?
Salt + Carbon dioxide + Water
What are the products of acid + metal oxide?
Salt + Water
What was the first acid-base theory?
Lavoisier - acids had to have oxygen in them
What disproves Lavoisier’s theory?
Acids such as HCl and H2S do not contain oxygen
What was Arrhenius’ acid-base theory?
Acids release protons, Bases release OH-
How is the Bronsted-Lowry theory different from Arrhenius’ theory?
The Bronsted-Lowry theory explains that a base is a proton acceptor. It also explains conjugate pairs
What is the equation for calculating pH using H+ conc.?
ph=-log(H+)
(H+) = 10^-pH
How do you calculate conc. of an acid when it is strong and monobasic?
(H+) = (acid)
How do you find the pH of a strong base?
Kw = (H+)(OH-)
pH=-log(H+)
What is Ka?
Acid dissociation constant
How do you work out Ka?
Ka= (H+)(A-) / (HA)start
Ka= (H+)^2 / (HA)
How do you find the conc. of a weak acid?
Use the Ka equation to find conc of H+
Then use this to work out pH
How do you calculate pKa?
pKa = -logKa
Ka = 10^-pka
What is the purpose of a buffer?
Buffers minimise changes in pH when small amounts of acid or base are added
What do acidic buffers include?
Weak acid and conjugate base
What is the buffer system in blood called?
Carbon acid-hydrogen carbonate buffer system
What are the reactions in the carbonic acid-hydrogen carbonate buffer system?
H2CO3 ⇌ H+ + HCO3-
H2CO3 ⇌ H2O + CO2
What is the name of the equipment that measures pH?
pH meter/ probe
