Unit 2 | Topics: Strength of Acids and Bases, properties of salts, dissociation, polyprotic, leveling effect

Question 1

Comparing Acids

Answer 1

by Ka or pKa, the one higher is the stronger acid

Question 2

strong acids

Answer 2

perchloric - HClO4
nitric - HNO3
sulfuric - H2SO4
HI, HBr, HCl

Question 3

Strong bases

Answer 3

LiOH
NaOH
KOH
Ca(OH)2
Sr(OH)2
Ba(OH)2

Question 4

Case 1: Salts that yield neutral solutions

Answer 4

If both ions are conjugate to a stronge acid or a strong base, then both ions show noa cid-base properties. Ions remain as ions in solution, result in neutral pH

Question 5

Case 2: Salts that yield weak acidic/basic solutions

Answer 5

If one ion has very weak properties, ie conjugate to a strong acid or a strong base, the other ion is a weak acid or base, then only the weak species is active and determines pH

Question 6

Case 3: Salts that are both weak acid and bases

Answer 6

if both ions are weak acid/ base, the pH is determined by the species with largest equilibirum constant. determine the acid and base, compare calculated Ka and Kb respectively

Question 7

weak acid/ base dissociation

Answer 7

1. compare K values to determine the dominant source of H3O+/ OH
2. make ICE table for dominant rxn
3. solve like a small K and do approximations

Question 8

percent dissociated

Answer 8

amount dissociated/ inital amount x 100