Acids and Bases (Physical) Flashcards
1
Q
Define Bronsted-Lowry acid
Define Bronsted-Lowry base
Define the reaction between the two.
A
- acid: proton donor
- base: proton acceptor
- reaction: reaction involving the transfer of a proton.
2
Q
Define:
- Monoprotic acid
- Diprotic acid
- Triprotic acid
A
- mono- acid that releases one H+ ion per molecule.
- do- acid that releases two H+ ions per molecule.
- tri- acid that releases three H+ ions per molecule.
3
Q
Give the definition of pH.
A
-log[H+]
(2d.p)
4
Q
Equation to find the concentration of H+ ions in a solution once another solution is added.
A
[H+] in original solution x (old volume / new total volume)
5
Q
Describe where Kw comes from.
What is the usual value for Kw at 298K?
A
Kw = Kc x [H2O]
- During; H2O —(reversible symbol)-> OH- + H+ reaction there is so much water that [H2O] is seen as a constant value, while [H+] and [H2O] are variables.
- As; Kc = ( [H+] x [OH-] ) / [H2O], therefore; Kc x [H2O] = [H+] x [OH-] and Kw = Kc x [H2O]
- This means; Kw = [H+] x [OH-]
Kw = 1 x 10^-14 mol^2dm^-6
6
Q
What is the effect of temperature on the pH and neutrality of water in terms of Kw?
A
H2O —(reversible symbol)-> OH- + H+ (—> exothermic)
- As temperature increases, equilibrium shifts right to endothermic direction to oppose increase.
- Therefore [H+] and [OH-] increase, Kw increases and pH decreases.
- However water still neutral as [H+] = [OH-]
7
Q
Give the definition of neutral
A
[H+] = [OH-]
8
Q
A