CDCP - 02.28.11 - Titration Excel Practice Example

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Table 01
Chemicals used for Titration of NaOH Lab
Name
Formula
Molar Mass (g/mol)
Acetic Acid (Vinegar)
CH3COOH
60.05
Sodium Hydroxide
NaOH
40.00
Potassium Hydrogen Phthalate KHC8H4O4
204.23
This is a table that displays the relevant properties for the chemicals used in the lab
Table 02
Titration for the Standardization of NaOH
Trial 1
Trial 2
Trial 3
Mass KHP (g)
1.165
1.276
1.345
Moles KHP (mol)
0.005704
0.006248
0.006586
Volume KHP (mL)
100.0
100.0
100.0
Molarity KHP (mol/L)
0.05704
0.06248
0.06586
V1 NaOH (mL)
0.23
0.56
0.05
V2 NaOH (mL)
23.08
24.01
26.41
VT NaOH (mL)
22.85
23.45
26.36
Avg Molarity of NaOH
Molarity of NaOH (mol/L)
0.2496
0.2664
0.2498
0.2553
This is table providing raw data for the Standardization of NaOH using KHP. The average molarity of NaOH was then used to titrate a
known volume of acetic acid (vinegar)
Table 03
Titration of Vinegar by NaOH
Trial 1
Trial 2
Trial 3
Trial 4
Trial 5
Molarity NaOH (mol/L)
0.2553
0.2553
0.2553
0.2553
0.2553
V1 NaOH (mL)
0.35
0.08
0.25
0.01
5.70
V2 NaOH (mL)
33.95
43.69
29.89
32.65
40.10
VT NaOH (mL)
33.60
43.61
29.64
32.64
34.40
Molarity Vinegar (mol/L)
0.8535
0.9089
0.7915
0.8375
0.8782
AVG Molarity of Vinegar
0.8539
Volume Vinegar (mL)
10.05
12.25
9.56
9.95
10.00
This is a table providing raw data for the titration of Vinegar (acetic acid) with NaOH. The average molarity of vinegar was then used
to determine the percent by mass of acetic acid in vinegar.
Table 04
Results
Experimental
Theoretical
Percent Error (%)
Molarity NaOH (mol/L)
0.2553
0.30
14.90%
Molarity Vinegar (mol/L)
0.8539
0.83
2.88%
%Acetic Acid in Vinegar
5.128
5.0
2.55%
This is a table to display the major results of the Titration Lab
Table 05
Equation
Example
Explanation
𝑉𝑑 = 𝑉𝑓 − 𝑉𝑖
𝑉𝑖 = 0.04 π‘šπΏ
𝑉𝑓 = 34.56 π‘šπΏ
𝑉𝑑 = 34.56 − 0.04 = 34.52 π‘šπΏ
This
calculation
was used for
finding the
volume of
NaOH
dispensed by
the buret in
both the
Standardizatio
n and
Neutralization
The mass of
KHP was
measured out
during the lab
and dissolved
into water, in
order for the
molarity to be
calculated the
#moles was
needed
The moles of
solute
dissolved in
1.0 L solution
is the
concentration
(molarity)
The titration
equation is
very similar to
the dilution
equation and
is used to
determine
equivalent
moles of each
This is the
simple
average,
calculated
since 2nd
grade 
The percent
error is a
display of the
difference
between the
accepted and
experimental
values
Volume Dispensed by buret
Calcul
ation
π‘šπ‘œπ‘™π‘’π‘ 
= π‘šπ‘œπ‘™π‘’π‘ 
π‘”π‘Ÿπ‘Žπ‘šπ‘ 
20.00 𝑔 𝐻2𝑂 π‘₯
1 π‘šπ‘œπ‘™ 𝐻2𝑂
= 1.11 π‘šπ‘œπ‘™ 𝐻2𝑂
18.02 𝑔 𝐻2𝑂
g --> mol conversion
π‘”π‘Ÿπ‘Žπ‘šπ‘  π‘₯
π‘šπ‘œπ‘™π‘’ π‘ π‘œπ‘™π‘’π‘‘π‘’
π‘™π‘–π‘‘π‘’π‘Ÿπ‘  π‘œπ‘“ π‘ π‘œπ‘™π‘’π‘‘π‘–π‘œπ‘›
Molarity
π‘€π‘œπ‘™π‘Žπ‘Ÿπ‘–π‘‘π‘¦ =
20 π‘šπ‘œπ‘™π‘’π‘ 
4.0 𝐿
When 20moles of solute is dissolved in 4.0 L of
solution, a 5.0 M solution results
π‘€π‘Ž π‘₯ π‘‰π‘Ž = 𝑀𝑏 π‘₯ 𝑉𝑏
0.5𝑀 π‘₯ 100π‘šπΏ = 0.25𝑀 π‘₯ 200π‘šπΏ
Titration
The amount of moles in 100 mL of 5.0M solution is
the same as that in twice the volume of diluted
solution ½ the concentration
Average
π΄π‘£π‘’π‘Ÿπ‘Žπ‘”π‘’ π‘œπ‘“ 𝐴&𝐡 =
% πΈπ‘Ÿπ‘Ÿπ‘œπ‘Ÿ = |
Percent Error
5.0 =
𝐴+𝐡
2
π‘‡β„Žπ‘’π‘œπ‘Ÿπ‘’π‘‘π‘–π‘π‘Žπ‘™ − 𝐸π‘₯π‘π‘’π‘Ÿπ‘–π‘šπ‘’π‘›π‘‘π‘Žπ‘™
| π‘₯100
π‘‡β„Žπ‘’π‘œπ‘Ÿπ‘’π‘‘π‘–π‘π‘Žπ‘™
5=
4% = |
4+6
2
25 − 24
| π‘₯100
25
The percent difference between the theoretical
and experimental values were calculated as 4%
Percent Acetic Acid in
Vinegar
π‘šπ‘œπ‘™ π‘Žπ‘π‘–π‘‘
𝑔 π‘Žπ‘π‘–π‘‘
𝐿 𝐻2𝑂
π‘šπΏ 𝐻2𝑂
π‘₯
π‘₯
π‘₯
π‘₯100
𝐿 𝐻2𝑂
π‘šπ‘œπ‘™ π‘Žπ‘π‘–π‘‘ π‘šπΏ 𝐻2𝑂
𝑔𝐻2𝑂
𝑔 π‘Žπ‘π‘–π‘‘
=
𝑔 𝐻2𝑂
0.83 π‘šπ‘œπ‘™ π‘Žπ‘π‘–π‘‘ 60.05 π‘Žπ‘π‘–π‘‘
𝐿 𝐻2𝑂
π‘₯
π‘₯
𝐿 𝐻2𝑂
π‘šπ‘œπ‘™ π‘Žπ‘π‘–π‘‘
1000π‘šπΏ 𝐻2𝑂
1 π‘šπΏ 𝐻2𝑂
π‘₯
π‘₯100 = 4.98%
1 𝑔𝐻2𝑂
The percent acetic acid in vinegar is found using
the molarity of vinegar found during titration, the
molar mass of vinegar, and known properties of
water
In order to
solve for the
percent acetic
acid in
vinegar, the
units must be
tracked and %
AA by mass
solved for
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