Proton transfer, acid-base chemistry, redox equilibria Flashcards
How do you work out the ionic product of water?
Kw = [H3O+][OH-] = 1×10^-14
What ions do acids produce in aqueous solutions?
H+ / hydronium ions H3O+
What ions do bases produce in aqueous solutions?
OH-
How are protons transferred in an acid-base reaction?
Proton is transferred from one acid to a base, with formation of another weaker acid + base.
What are conjugate acid/base pairs?
Pairs of substances which differ by a single proton.
What are amphoteric substances?
Substances that can accept or donate protons - acts as either an acid or base.
Does ‘strength’ of an acid equal concentration?
Strength does NOT equal concentration!
What does the acid ‘strength’ of an aqueous solution depend on?
Concentration of hydronium ions (H3O+)
- conc of H3O+ α acidity
How do you find the pH with H3O+?
-log10[H3O+]
How do you find [H3O+]?
10^-pH
What does Kw control the balance of?
H3O+ and OH-
What is [H3O+] compared to [OH-] when the pH is 7?
neutral so [H3O+] = [OH-]
What is [H3O+] compared to [OH-] in acidic solutions?
[H3O+] > [OH-]
What is [H3O+] compared to [OH-] in alkaline solutions?
[H3O+] < [OH-]
How do strong acids diff to weak acids?
They completely ionizes in aqueous solutions
How do weak acids diff to strong acids?
They partially dissociate in water to form a few ions in aqueous solutions
Do strong acids have strong or weak conjugate bases?
Weak - effectively do not function as bases
What conjugates do weak acids/bases have?
Weak conjugates
Do strong bases have strong or weak conjugate acids?
Weak - effectively do not function as acids
What is the Henderson-Hasselbalch equation for acids?
HA + H20 ⇌ A- + H30+
What is Ka?
acid dissociation constant
What is the Ka of acids in the Henderson-Hasselbalch equation?
Ka = [A-][H30+] / [HA]
How do you find pKa from Ka?
pKa = -log10[Ka]
What is the pH of acids in the Henderson-Hasselbalch equation?
pH = pKa + log10[A-]/[HA]
What is the Henderson-Hasselbalch equation for bases?
B + H20 ⇌ BH+ + OH-
What is the Kb of bases in the Henderson-Hasselbalch equation?
Kb = [OH-][BH+] / [B]
What is the pOH of bases in the Henderson-Hasselbalch equation?
pOH = pKb + log10[BH+]/[B]
How do you work out Kw for acid-base conjugate pairs?
Ka x Kb = Kw
pKa x pKb = pKw
What pH is pKw at RT?
pH 14
How do you find pKw from Kw?
pKw = -log(Kw)
