Chapter 8 Test Flashcards
How do you answer the questions asking you about changing volumes of a solution?
You will try to always change it to a multiple of 10
What pH are bases?
Anything greater than 7
What pH are acids?
Anything less than 7
The smaller the _______, the larger the _________, the weaker the acid/base.
Ka/Kb, pKa/pKb
How would you determine the concentration of an acid by using the base’s equivalence point on a titration curve?
Multiply the mL/L of the equivalence volume times the concentration of the base times the mole ratio between the two(acid and base). Then divide the moles by the volume of the acid.
How do you solve equations with a weak acid and a strong base if the weak acid is in excess?
- Same goes for weak base/strong acid
The resulting solution is a buffer. So use the Henderson-Hasselbach equation to determine the pH.
What does a strong acid/strong base titration curve look like?
Its equivalence point is at a pH of 7. If a base is being added to an acid that will affect the shape also.
What can you remember about monoprotic strong acids and their concentrations?
The concentration of the acid is equal to the concentration of the hydronium ions
How do you solve equations with a weak acid and a weak base?
They will go to equilibrium so you use ice tables
Titrant
The solution with the known concentration in the burette
Is Ka or pKa often used for weak acids?
pKa
How do you write dissociation equations?
Acid + Water yields conjugate base and hydronium
Base + Water yields conjugate acid and hydroxide
When should you use a single arrow? What about double arrows?
Single arrows for anything strong because it completely dissociates
Double arrows if there are two weak things
If the same acid has two different concentrations, the solution of lower concentration will have a ________ percent ionization.
Higher
What is the pH of water and what happens to the pOH?
They are both 7 because pure water is neutral, however, if the temperature is not 25 degrees celsius then you know pH and pOH will always be the same
Analyte
The solution with the unknown concentration in the beaker
What do the values generally look like for Ka/Kb values of weak acids/bases?
The values are smaller than 1 because these reactions do not go to completion
How do you solve equations for weak acids? For strong acids?
You need an ice table; You can just do the equations on the equation sheet
Acid
Donates hydrogen ions
What do the values generally look like for Ka/Kb values of strong acids/bases?
The values are larger than 1 because these reactions go to completion
How do weak acids often look in particle diagrams?
Unionized, mainly reactants because they didn’t dissociate completely
The smaller the _______, the larger the _________, the stronger the acid/base.
pKa/pKb, Ka/Kb
Base
Receives hydrogen ions
What should you remember when writing net ionic equations with strong bases or acids?
The part that isn’t H+ or OH- is a spectator ion. Remember to just leave that part out when writing the net ionic equation