Includes definitions, various titration reactions and their characteristics. Finding end point, standardisation and indicators.
Includes examples of:
- Precipitation titrations
- Complexometric titrations
- Iodine titrations
- Permanganate titrations
Sample
solution solution
j b tha
known c Unknown c
Reaction
known V Known V complete
required for
complete reaction
Titrant reagent
Titrand analyte
Equivalence point Exact right V of
titrant has been added to react
with the
analyte
Types of titration reactions
10h Combination
Acid Base reactions change in pH
Precipitation reactions solid is formed
complexation reactions complex is formed
, I I 1
Electron transfer reactions
Redox reactions Electrons are
transferred between titrant analyte
characteristics
Speed up the process by heating
or adding a
catalyst
complete reactions with NO
alternative reactions
Understand the
i e
chemistry of
the reaction different pH
cause parallel reactions 0
may
Finding equivalence point
reaction
Following by
7 Consumption of a reactant
2 Production of a product
, I
Primary reagent indication
Color change due to reactants
End point indicator changes color
ideally endpoint equivalence point
instrumental indication
conductivity voltage
Ancillary reagent indication
i e indicator
standardisation
It is vital to know accurately the
concentration of titrant
GREAT
characteristics of primary standard
A readily available solid
Known composition
Can be weighed dry pure
Stable solution doesn't vary in
conce
time
over tration
, Reacts with titrant via suitable reaction
Preferably high molecular weight
less susceptible to degradiation
Doesn't likely to evaporate
Titrant Standard Name
HCl Nato Sodium carbonate
NaOH KOOCCettucOOH Potassium acid phthalate
AGNO NaCl sodium chloride
NaCl AgNOs Silver nitrate KHP
COTA PUNO z Lead nitrate
KMnon COON a a Sodium oxalate
WILL BE ON THE EXAM
1 Make solution of standard
2 Make primarystandard
3 Titrate primary standard with titrant
4 Calculate concentration of titrant
5 Titrate sample with titrant
6 Calculate concentration of analyte
, concentration c mass of substance
per unit volume g dm
1 m CV
omol1dm
Molarity
Loa.k.a molar concentration is
the number of moles per unit
volume
I
y Mn M
Stoichiometry The ratio of moles of
reactants included in a reaction
, Ht
pH log
Ht low pH
High
Low Ht high pH
Indicators
Acid strong strong weak weak
Base strong weak strong weak
7 27 7 rev act
pH
endpoint 6.9 3.5 9.5
indicator bromothymol methyl phenol
blue orange phthalein
color change
O
Remember acid base combination
and indicator used
, PH meter gives titration curve
is
it
I
i'go 1 equivalence
I point
8 I I
z T
i
I f
n I l
3 i i
iI
7
acid added Ccm
Precipitation Titrations
AGNO NaCl Agclcppts NANOS
1 L RATIO
Aga is extremely insoluble
saturated solution contains
1EIgdm
potassium chromate used as an
indicator KzCrOu
Red in presence of excess Ag ions
to Agzcron
The benefits of buying summaries with Stuvia:
Guaranteed quality through customer reviews
Stuvia customers have reviewed more than 700,000 summaries. This how you know that you are buying the best documents.
Quick and easy check-out
You can quickly pay through credit card for the summaries. There is no membership needed.
Focus on what matters
Your fellow students write the study notes themselves, which is why the documents are always reliable and up-to-date. This ensures you quickly get to the core!
Frequently asked questions
What do I get when I buy this document?
You get a PDF, available immediately after your purchase. The purchased document is accessible anytime, anywhere and indefinitely through your profile.
Satisfaction guarantee: how does it work?
Our satisfaction guarantee ensures that you always find a study document that suits you well. You fill out a form, and our customer service team takes care of the rest.
Who am I buying these notes from?
Stuvia is a marketplace, so you are not buying this document from us, but from seller remsuville. Stuvia facilitates payment to the seller.
Will I be stuck with a subscription?
No, you only buy these notes for £3.49. You're not tied to anything after your purchase.
