Know the definitions of Arrhenius, Bronsted-Lowry and Lewis acids and bases. – Arrhenius: Acid dissolved in water increases conc. Of H+ ions. Base dissolved in water increases conc. Of OH- ions – Bronsted-Lowry: Acid: substance that donates a proton to another substance Base: substance that accepts a proton from another substance -Lewis: Acid: electron pair acceptor Base: electron pair donor Be able to Identify Arrhenius, Bronsted-Lowry and Lewis acids and bases In an acid- base reaction equation.
Understand the concept of conjugate acid-base pairs and how each member differs from the other by one proton. -conjugate base formed by removing a proton from the acid -conjugate acid formed by adding a proton to the base Be able to write and identify conjugate acid-base pairs. understand that acid-base reactions are proton transfers Involving two sets of conjugate acid-base pairs, – The stronger an acid, the weaker Its conjugate base, and the stronger a base, the weaker its conjugate acid. -Strong acid completely Weak acid partially dissociates in water, mixture of acid and conjugate base: the conjugate base of a weak acid is a weak base. egligible acidity has some hydrogen but does not behave like acid in water: conjugate base is strong base in substance with negligible acidity. -When X- is a stronger base than H20, equilibrium lies to left. HX is a weak acid -In every acid-base reaction, equilibrium favors transfer of the proton from the stronger acid to the stronger base to form the weaker acid and the weaker base. -Kc (equilibrium constant) 1 (right) Know that water auto-ionizes into hydrogen ions and hydroxide ions, expressed by Kw, the ion product of water. – – @ 25C : Kw=l . 0X10-14 Know how to calculate hydrogen ion and hydroxide ion concentrations using Kw.
Kvv= 1. 0X10-14 Be able to interconvert pH, pOH, [H+] and [OH-I. – pH= -log[H+] – POH= -log[0H-] – pH+pOH=14 Understand how the strength of an acid relates to its extent (%) of ionization into – stronger the acid, higher % ionization Know the definitions of strong and weak electrolytes. -strong acids are strong electrolytes, weak acids are weak electrolytes Know how to write the acid ionization constant (Ka) expression for a weak acid. 1 . Write ionization equilibrium 2. Write out Ka 3. Write ice chart 4. Solve for x : Solve for Ka, or Concentration of [H+] from Ka=products/reactants 5. onization= x 100% Know that the pKa is -log of Ka. pKa= acid dissociation constant Know how to convert between Ka and pKa. Understand how the magnitude of Ka and corresponding pKa reflect the strength of the weak acid. Understand and be able to write the ionization constant (Kb) expression for a weak base. – Understand how the magnitude of Kb reflects the strength of the weak base. – higher Kb means stronger base Know that the percent ionization of a weak acid increases as its concentration decreases. Be able to predict the acidity (acidic, basic or neutral) of a salt solution from the ature of the anion and cation.
Be able to perform calculations such as: determining the Ka of a weak acid from pH calculating pH from Kb of A- and initial calculating Ka or Kb if the other is known (via Kw = KaKb) Know that the unknown “x” may usually be dropped if the Ka or Kb being utilized has a value of 7. 0 at equivalence because it forms a weak conjugate base which increase pH slightly Know that a titration of strong acid with weak base produces an acidic solution at the equivalence point. -Forms weak conjugate acid, thus making it slight acidic, pH Ksp, precipitation occurs – Q=Ksp, equilibrium exists