Chapter 10 - Acid and Base Titrations Flashcards
For each type of titration, the goal is usually to construct a graph showing how ________
pH changes as titrant is added
What are the three different regions of the pH titration curve for different calculations?
Pre-equivalence point equivalent point (measuring the endpoint) post-equivalence point
Strong Acid - Strong Base Titrations
- write _______ reaction
- For strong-strong, the amount ______ will consume a stoichiometric amount of ______
- find what point?
- chose your tirant ____ and ____
- what is the pH at the equivalence point?
- chemical
- H+, OH-
- equivalence
- volumes, calculate
- 7
- In strong acid - strong base, what happen at the equivalence point?
- is the pH at the equivalence point always be in a strong acid-strong base?
- number of moles of NaOH equals the moles of HCl in the solution
- pH = 7
Weak Acid - Strong Base
1. How is it similar to Stong-Strong in terms of mole and pH?
- How is it different in terms of pH?
- what happens at the equivalence point?
- Before and after equivalence point use ______ ________
- the moles have to equal and increasing the amount of base raise pH
- The pH will be low but higher than strong acid
- pH will be basic because all the acid is converted into conjugate base and pH at the equivalence point will be slightly above 7
- ICE Table
The volume of at the equivalence point of acid-base titration depends on……
- acid
- base
amount of moles acid present in solution before titration begins and on the concentration of the base added
Strong Acid - Weak Base
Same as Weak Acid - Strong Base, except at the equivalence point the pH is …..
below 7
What is the buffer region?
pH = pKa
region at the half equivalence point or midpoint
Polyprotic Acids
How many equivalence point diprotic acids have?
How many equivalence point triprotic acids have?
The first equivalence point volume is the same volume as the ________
2
3
second equivalence point
Titration Analysis
What are the three common analysis.
derivative plots
gran plots
indicators
Derivatives of Titrations:
1st derivative: Examines the___________
2nd derivative: Examines the _______
- slope of the curve
2. rate change of the slope
Gran Plots
- how does determine equivalence point
- what does it assumes about one mole of strong base?
- why is a little more accurate that derivative plots?
- uses data obtained prior to the endpoint
- one mole of strong base will consume on mole of acid
- no delay from pH electrode
Indicators
1. what are they and what do they have
- they are weak acid/base with protonated and deprotonated forms of
Kjeldhal Nitrogen Analysis
- what is this method used for?
a. what do you boil (digest) the substance in? - The solution is made _____ and the liberated ___ steam is distilled into a receiver with a known amount of ____.
- Excess, unreacted HCl is then titrated with standard NaOH to determine …..
- determining nitrogen in organic substances
a. sulfuric acid - basic, ammonia, HCl
- how much HCl was consumed by ammonia