Acid-Base Chemistry Flashcards
Describe Arrhenius Theory
- focus on electrolytes
- ACIDS ionize to produce H+ (aq) IONS
- BASES ionize to produce OH- (aq) IONS
- weakness: limited scope eg. NH3 basic but lacks OH-
Describe Brønsted-Lowry Theory
- Focus on H+
- ACID = H+ DONOR
- BASE = H+ ACCEPTOR
- describes conjugate acids/bases
- h20 AMPHIPROTIC (can donate or accept H+)
Describe Lewis Theory
- Focus on electrons
- ACID = e- pair acceptor
- BASE= e- pair donor/e- pair shared
- least restrictive definition: describes aq and non aq solvents, protic and non-protic acids
What defines the strength of an acid/base
- ACID - ability to protonate water/generate H30+ ions
- BASE - ability to create OH- in water
- completely disassociate in water
- Ka/Kb»_space; 1 (products dominate)
What defines a weak acid/base
Ka/Kb < 1 (reactants dominate)
Name strong acids
HCl HBr HI HClO4 HNO3 H2SO4
Name strong bases
Gp 1&2 hydroxides
Gp 1&2 hydrides (H-)
Gp 1&2 oxides (O2-)
Relationship between acid-base conjugates
the stronger the acid/base, the weaker its conjugate
Define amphiprotic
can undergo autoioniziation/substance ionizes itself
water is amphiprotic
Kw value
1x10^-14
AT 25 degrees C!!!
Relationship between pKa/Kb and Ka/Kb
Inversely related
pH and pOH equations
pH = -log[H3O+] pOH = -log[OH-]
Strong acids and bases in terms of behaviour in water, Ka/Kb, pKa/Kb and conjugate pair property
- complete ionization in water
- Ka/b > 1
- pKa/b < 0
- conjugate negligable
Weak acids and bases in terms of behaviour in water, Ka/Kb, pKa/Kb and conjugate pair property
- partial ionization in water
- Ka/b 10^-14 to 1
- pKa/b 10^-14 to 1
- conjugate weak
Negligible acids and bases in terms of behaviour in water, Ka/Kb, pKa/Kb and conjugate pair property
- Negligible ionization in water
- Ka/b < 10^-14
- pKa/b >1
- conjugate strong
