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Titration Calculations:
Revision Summary
Number 59
1
C
hem
F
actsheet
www.curriculumpress.co.uk
To succeed with this topic you need to know and understand the material
covered so far in Factsheets No. 7 (Moles and Volumetric Analysis), No.23
(How to Answer Questions on Titration Calculations), No.51
(‘Redox
Equilibria (IV) : Redox Titrations’) No.57: Answering questions on Redox
Titrations 1)
The purpose of this Factsheet is to bring together all the different
types of titration calculations under various categories.
By now you should be competent in titration calculations. If you can now
recognise a calculation problem as belonging to a particular category it will
help you to get into the problem more quickly.
You should regard this Factsheet as a
summary
of all the four Factsheets
listed above. We will revisit the basic equations and terms, and then put in
the categories.
TERMS USED
Volumetric analysis

this is another way of saying TITRATION i.e.
adding reacting solutions together to find the exact point (the end
point) when the two solutions have completely reacted together.
Standard Solution

a solution made by dissolving an
accurate
amount
of solid in, usually, water. The volume is usually 250cm
3
so you can
always
calculate g dm
3
. If the
M
r
is known, you can calculate mol dm
3
.
Titre

the final volume added from the burette in the titration. When
a series of titrations are done, then titres in good agreement (concordant)
are averaged to give the volume used in calculations – the
AVERAGE
TITRE.
Acid/Base Titration

as it says! An acidic solution reacting with a
basic solution (neutralisation).
Redox Titration

the two half equations are combined to give the
balanced chemical equation (using the ‘electron balancing method’).
One of the half equations is a reduction process (electron gain) and the
other an oxidation process (loss of electrons)
EQUATIONS USED IN CALCULATIONS
moles
=
grams
A
r
/
M
r
moles
=
volume (cm
3
)
×
M (mol dm
3
)
1000
purity percentage
=
mass of pure
×
100
mass of impure
percentage by mass
=
mass of element
×
100
mass of compound
CATEGORIES OF TITRATION CALCULATIONS
•
categories 1, 2, 3, 4 and 5 use examples from both redox and acid/
base titrations.
•
category 6 is usually only acid/base titration type.
1
Finding concentration
of a solution
2. Finding the
formula mass
(
M
r
)
of a compound
3. Finding the
percentage
purity
of a sample of impure
compounds
4. Finding the
formula
of a
compound
5. Finding the
percentage
mass
of an element in a
compound
6. Using the
'back titration'
method
A standard solution is made and
used to find the concentration of
the other solution in the titration.
A standard solution is made of the
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This note was uploaded on 03/08/2011 for the course CHEM 101 taught by Professor Hard during the Spring '11 term at UT Arlington.
 Spring '11
 hard
 Mole

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