Ionic Equillibrium Flashcards
Arrhenius concept of Acid and Base?
Acid ionizes in water to give H+ ion
eg. HCl, H2SO4, HNO3
Base ionizes in water to give OH- ion
eg. KOH, NaOH
Limitations of Arrhenius Concept?
1) Water insoluble acid and bases
2) Formation of H3O over H+ ion
3) Oxides of non metals are acidic
Eg. CO2, SO2, SO3
4) Oxides of metals are basic
Eg. Na2O, CaO, MgO
5) Acidic properties of AlCl3, FeCl3 and
Basic properties of NH3
6) Can’t explain acid base reactions like
Formation of NH4Cl
Bronsted- Lowry Concept of Acids and Bases?
Acid can donate one or more proton to another chemical species.
Base can accept one or more proton from another chemical species.
Conjugate acid base pair?
A pair of acid and bases that differ by a single proton and can be converted from one to the other by gain or loss of a proton is called conjugate acid base pair.
Examples of Amphoprotic substances?
H2O, HSO4-, HCO3-
Limitation of Bronsted- Lowry concept?
1) Acidic properties of CO2, SO2, SO3
2) Basic properties of Na2O, CaO, MgO
3) Acidic properties of AlCl3, FeCl3 and
Basic properties of NH3
4) Non protic transfer acid base reaction
like formation of CaCO3
Lewis Concept of Acids and Bases?
Acids are chemical species that can accept lone pair of electrons from other species to form coordinate covalent bond.
Bases are chemical species that can donate lone pair of electrons from other species to form coordinate covalent bond.
Limitation of Lewis Concept?
1) Cannot explain strength of acids and bases
2) Says acid base reactions are slow processes since coordinate covalent bonds take time to form but it’s actually a fast process.
Factors affecting degree of ionization?
Nature of electrolyte
Nature of solvent
Temperature
Dilution
Presence of other ions
State Ostwald’s Dilution Law
The degree of ionization is inversely proportional to the square root of concentration of the electrolytic solution
Limitations of Ostawald’s Dilution Law
Applicable only for weak electrolytes.
Solubility product (Ksp)
Product of concentration of ions in its saturated solution at a particular temperature.
Ionic Product (Ip)
Product of ions in a solution
(saturated, unsaturated or supersaturated)
Conditions for saturation of solution?
If Ip > Ksp —> super saturated.
If Ip = Ksp —> saturated.
If Ip < Ksp —> unsaturated.
Buffer solution?
Solution that maintains its pH fairly constant or resists change in pH.
