Department of Process Engineering
Chemical Engineering D 316
Report 1B: Solvent Extraction
Ms. EJ Pool
23631406
Group 12
10 March 2023
© Stellenbosch University
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i
Abstract
This practical involves the extraction of copper (II) and iron (III) from a pregnant leach solution which
was prepared from Fe3+ solution and CuSO4.5H2O crystals. The provided organic phase is mixed with
the aqueous phase (PLS), and an oxime extractant diluted in kerosene is used to facilitate the process.
Different organic and aqueous solution ratios are used, and some are done in triplicate. Diluted
solutions of the PLS and aqueous solutions were sent to a laboratory to undergo an ICP analysis. The
results of these analyses were then used. Three different concentrations of the oxime extractant
diluted in kerosene are used (8%, 12%, and 16%) and by analysis of equilibrium curves, regression
models, percentage of copper (II) and iron (III) extracted and selectivity towards copper (II), it is found
that the extractant concentration best suited to this procedure is the 12% extractant concentration.
Furthermore, after analysing the triplicate experimental data points, it is found that the 8 % and 16 %
extractant concentration data have a great uncertainty.
ii
Table of Contents
Plagiarism Declaration ............................................................................................................................. i
Abstract ................................................................................................................................................... ii
Table of Contents ................................................................................................................................... iii
Nomenclature ........................................................................................................................................ iv
1
Introduction .................................................................................................................................... 5
2
Theory / Literature .......................................................................................................................... 5
3
4
2.1
Pregnant Leach Solution ......................................................................................................... 5
2.2
Solvent Extraction ................................................................................................................... 5
2.3
ICP spectroscopy analysis for aqueous samples ..................................................................... 6
2.4
Mole balance for determining organic phase concentrations................................................ 6
Methodology................................................................................................................................... 6
3.1
Experimental plan ................................................................................................................... 6
3.2
Equipment and materials ........................................................................................................ 7
Results and Discussion .................................................................................................................... 8
4.1.1
Equilibrium curves for copper and iron at 8 vol%, 12 vol% and 16 vol% oxime diluted in
kerosene (extractant) and regression ............................................................................................. 8
4.1.2
Percentage Cu2+ and Fe3+ extracted ................................................................................ 9
4.1.3
Selectivity towards copper (II) ...................................................................................... 10
4.1.4
Performance of the solvent .......................................................................................... 11
5
Conclusions and Recommendations ............................................................................................. 12
6
References .................................................................................................................................... 12
Appendix A.
Experimental Results..................................................................................................... 13
Raw data for Copper(ll) and Iron(lll) obtained from ICP analysis ..................................................... 13
Appendix B.
Processed Data.............................................................................................................. 15
Equilibrium curve data ...................................................................................................................... 15
Regression data................................................................................................................................. 17
Appendix C.
Typical Calculations ....................................................................................................... 18
iii
Nomenclature
Symbols
n
mole
mol
m
Mass
g
V
Volume
ml
Density
kg/m3
Greek symbols
ρ
Subscripts and superscripts
aq
In the aqueous phase/solution/layer
org
In the organic phase/solution/layer
Acronyms
PLS
Pregnant Leach Solution
ICP
Inductively Coupled Plasma
iv
1 Introduction
When two immiscible solvents differ in their solubility or distribution coefficient, a molecule is
extracted from one solvent into another during solvent extraction (H & L, 2017). Applications of this
process in industry include water effluent treatment, extraction of rare earth metals, purification of
substances, and reprocessing of nuclear waste (D & F, 2022). The two main aims of this practical are
understanding a typical solvent extraction procedure and evaluating the extractant's performance in
this process. These aims will be met by creating equilibrium curves for copper and iron for the data
acquired at different concentrations of the extractant, creating a line of regression, calculating the
distribution ratio and percentage extracted of both copper and iron as a function of the O/A ratio
tested and discussing the performance of the solvent and its concentration on phase equilibrium as
well as the extraction of and selectivity towards copper.
2 Theory / Literature
2.1 Pregnant Leach Solution
Pregnant leach solution or PLS is used in solvent extraction and electrowinning processes. For direct
manufacturing of high-purity cathodes, the pregnant leach solutions from leaching are excessively
diluted and impure. These solutions would produce impure copper deposits after electrowinning. To
create pure, high-copper electrolytes from diluted, impure pregnant leach solutions, solvent
extraction is used. (WG, 2001)
2.2 Solvent Extraction
The PLS is combined with an organic liquid that contains an extractant during solvent extraction. The
goal is to promote the development of soluble in the organic phase organometallic complexes
between the target metal species in the aqueous phase and the extractant, ensuring that the resulting
complex remains in the organic phase. Due to the difference in solubility or distribution coefficient
between two immiscible (or barely soluble) solvents, the process of solvent extraction involves moving
a chemical from one solvent to another. (M.H.I, 2016) Gravity helps to separate the two phases since
the aqueous layer is denser than the organic layer. The preferred extractants for copper extraction
are oximes, and equation [1] can be used to define the general reaction wherein the extractant and
copper produce the organometallic complex through ion exchange.
2+
+1
[1] Equation 1: 𝐶𝑢𝑎𝑞
+ 2𝑅𝐻𝑜𝑟𝑔 ↔ Cu𝑅2,𝑜𝑟𝑔 + 2𝐻𝑎𝑞
5
Where RH denotes the extractant with proton H+, and the subscripts “aq” and “org” denote
species in the aqueous and organic phases respectively.
2.3 ICP spectroscopy analysis for aqueous samples
An analytical technique called ICP (Inductively Coupled Plasma) Spectroscopy is used to find and
quantify components in chemical sample analysis. In this process, a sample is ionized by a very hot
plasma, often formed of argon gas. The middle of the plasma is cut through by a gas flow, which results
in a channel that is colder than the surrounding plasma but still significantly warmer than a chemical
flame. A nebulizer is typically used to generate a liquid mist before releasing the sample into the
central channel to be analysed. (F, 2012)
2.4 Mole balance for determining organic phase concentrations
In order to create the equilibrium curves, the moles of copper and iron in the organic phase must first
be calculated by equation [2] and then converted to concentration.
[2] Equation 2: 𝒏𝒐𝒓𝒈 = 𝒏𝑷𝑳𝑺 − 𝒏𝒂𝒒
Equation [3] will be used for extraction isotherms and to assess regression.
[3]
Equation 3: [𝑪𝒖𝟐+
𝒂𝒒 ]
Where Keq =
=
[𝑪𝒖𝟐+
(𝒐𝒓𝒈) ]
𝑲𝒆𝒒 ([𝑹𝒕𝒐𝒕𝒂𝒍] − 𝟐[𝑪𝒖𝟐+
(𝒐𝒓𝒈) ])
[𝐶𝑢𝑅2 (𝑜𝑟𝑔)]
2+
[𝐶𝑢 (𝑎𝑞)][𝑅𝐻(𝑜𝑟𝑔)]2
is the equilibrium constant and [𝑅𝑡𝑜𝑡𝑎𝑙 ] = [𝑅𝐻(𝑜𝑟𝑔)] +
2[𝐶𝑢𝑅2 (𝑜𝑟𝑔)]
3 Methodology
3.1 Experimental plan
Firstly, the PLS was made as the aqueous layer. This was then mixed with the organic solution. The PLS
and organic solution were mixed at different ratios and an oxime extractant diluted in kerosene was
added to facilitate with the extractant process. Some of these ratios were done in triplicate to test
their repeatability. Samples of the diluted aqueous phase and PLS were then sent to a laboratory for
6
an ICP analysis to determine the concentration of copper and iron in said samples. The results
obtained from the ICP analysis is in Appendix A.
3.2 Equipment and materials
The equipment required for this practical is as follows:
• 5 x magnetic stirrers
• 9 x separation funnels
• 1 x 50 ml, 1 x 100 ml measuring cylinder (to be used for the aqueous phase only)
• 1 x 10 ml, 1 x 50 ml and 1 x 100 mL measuring cylinder (for the organic phase)
• 3 x glass funnels
• 10 x 100 ml, 10 x 250 ml and 2 x 600 mL glass beakers
• 5 x 10 cm watch glasses to cover beakers
• 13 x 100 ml volumetric flasks for dilution of samples
• 1 x 1000 – 5000 μL variable pipette (and associated tips)
• 1 x pH meter
• 1x laboratory mass balance
The chemicals required for this practical are as follows:
• The organic phase: 8 vol%, 12 vol%, and 16 vol% LIX 984N-C (an oxime extractant supplied by BASF)
diluted in kerosene.
• (Assume that the molecular weight of the organic extractant is 263 and has a density (25 °C) of
approximately 0.94 g/cm3 ).
• For the aqueous phase prepare approximately 7.4 g/L Cu2+ and 4.5 g/L Fe3+, by addition of
CuSO4·5H2O and Fe2(SO4)3·xH2O crystals to demineralized water.
• Dilute sulphuric acid (0.05 M H2SO4).
• Concentrated sulphuric acid (98% H2SO4).
7
4 Results and Discussion
4.1.1 Equilibrium curves for copper and iron at 8 vol%, 12 vol% and 16 vol%
oxime diluted in kerosene (extractant) and regression
The aqueous phase concentration of copper and iron was obtained from the ICP analysis. The
concentration in the organic phase was calculated using the mole balance, [2] Equation 2. The sample
Concentration in organic layer (mol/L)
calculations are available in Appendix C.
8 % LIX
12 % LIX
16 % LIX
Линейная (8 % LIX)
Линейная (12 % LIX)
Линейная (16 % LIX)
3,5
3
2,5
2
1,5
1
0,5
0
0
0,001
0,002
0,003
0,004
0,005
0,006
Concentration in aqueous layer (mol/L)
Figure 1: Equilibrium curves for copper at 8 vol%, 12 vol% and 16 vol% extractant diluted in kerosene
and regression
As depicted in Figure 1, the experimental data used for the extractant concentrations of 8% and 16%
appear to be spread out and have no apparent linear form. Because of this, the equilibrium
experimental data points do not fit the linear regression analysis for the respective extractant
concentrations well. However, the experimental data used for the extractant concentration of 12%
are less spread out and thus fit the linear regression analysis relatively well. This means that there is
a relatively good fit of the linear regression analysis to the experimental data for an extractant
concentration of 12%.
8
Concentration in organic layer (mol/L)
8 % LIX
12 % LIX
16 % LIX
Линейная (8 % LIX)
Линейная (12 % LIX)
Линейная (16 % LIX)
2
1,5
1
0,5
0
0
0,001
0,002
0,003
0,004
0,005
0,006
Concentration in aqueous layer (mol/L)
Figure 2: Equilibrium curves for Iron at 8 vol%, 12 vol% and 16 vol% extractant diluted in kerosene
and regression
As depicted in Figure 2, the experimental data used for extractant concentrations of 8% and 16% also
appear to be spread out and have no apparent linear form, whilst the experimental data used for an
extractant concentration of 16% appear to be less spread out and has some linear form. This means
that the equilibrium experimental data used for extractant concentrations of 8% and 16% do not fit
the linear regression analysis well, while the data points used for an extractant concentration of 12%
has a relatively good fit of the linear regression analysis.
4.1.2 Percentage Cu2+ and Fe3+ extracted
Table 1: Percentage of Copper (II) and Iron (III) extracted with respect to the O/A ratios tested using
averaged triplicate experimental points.
Extractant
Concentrations
Ratios (O/A)
04:01
03:01
02:01
01:01
01:02
01:03
01:04
8%
Cu
Fe
98.275293 93.035318
98.178954 92.958318
97.56442 95.342212
97.3879 97.627736
97.038484 97.970526
95.69431 97.440822
97.047119 98.368052
9
12%
Cu
Fe
98.9206228 94.904544
99.2620457 94.779803
99.1386594 96.481474
98.2157944 97.274975
97.844476 98.108844
97.5451724 98.178626
97.9910803 98.612145
16%
Cu
Fe
98.257193 97.7729951
97.935085 96.4800663
97.819522 97.0606108
96.864251 96.9539563
98.119231 98.7144169
95.915262 97.2707471
98.26008 98.8542166
Table 2: Percentage of Copper (II) and Iron (III) extracted with respect to the O/A ratios tested for
the triplicate experimental data points.
Triplicate ratios (O/A)
Extractant Concentrations
1
2
3
Difference between largest
and smallest value
01:02
01:02
01:04
8%
12%
16%
Cu
Fe
Cu
Fe
Cu
Fe
96.831317 97.803069 97.9545918 98.21286
98.136314
98.801414
97.571241 98.327083 97.7920014 98.052477
98.135934
98.742738
96.712894 97.781427 97.786835 98.061193
98.507993 99.0184978
0.8583466
0.5456555 0.16775679 0.1603831
0.3720584
Table 1 shows that when the ratio of organic to aqueous phase tested is greater than one, the
percentage of copper (II) extracted is greater than that of iron (III). When the ratio is greater than or
equal to one, the extractant percentage of copper (II) is only greater than that of iron (III) for an
extractant concentration of 12 %.
According to Table 2, the triplicate experimental data points at an extractant concentration of 8% vary
greatly. At 16 %, they vary less and at 12 % the triplicate experimental data points are the most
consistent and similar. At an extractant concentration of 12 % the difference between the largest and
smallest data point is the smallest at roughly 0.17 and 0.16 for copper (II) and iron (III) respectively.
4.1.3 Selectivity towards copper (II)
Ratios
Table 3: Distribution ratios using averaged triplicate experimental data points.
Extractant
Concentrations
8%
12%
16%
04:01
03:01
02:01
01:01
01:02
01:03
01:04
5.064011469
4.84913592
2.396379687
1.136030909
0.85703104
0.742288543
0.690109062
5.915937556
8.866610998
5.119203665
1.912422745
1.097321568
0.927639153
0.86354392
1.598624495
2.133693727
1.687286787
1.215409991
0.854506615
0.834874926
0.823042885
10
0.27575987
Table 4: Distribution ratios for the triplicate experimental data points.
Triplicate ratios (O/A)
Extractant Concentrations
1
2
3
Difference between largest and smallest value
01:02
01:02
01:04
8%
12%
16%
0.866584 1.0928759 0.80377742
0.8610087 1.1033059 0.84305269
0.8435005 1.0957829 0.82229854
0.0230835
0.01043 0.03927527
Table 3 indicates that the 16 % extractant concentration has the worst selectivity due to its low
distribution ratios, an 8 % extraction concentration has a better selectivity, and a 12 % extractant
concentration has the best selectivity given its high distribution ratios.
With reference to Table 4, the 12 % extractant concentration has the smallest difference of
approximately 0.01 between the largest and smallest triplicate experimental data points.
4.1.4 Performance of the solvent
Based on Table 2 and Table 4’s findings, the 8 % and 16 % extractant concentrations have the greatest
uncertainty and thus a 12 % extractant concentration would have the most accurate data.
Given that, for an extractant concentration of 12 %, the percentage of copper (II) extracted is the
highest (Table 1), the selectivity is the highest (Table 3) and the uncertainty based on the triplicate
experimental data points is the lowest (Table 2 and Table 4), it can be said that an extractant
concentration of 12 % would be the best choice.
Furthermore, the equilibrium curves for copper (II) and iron (III) depicted in Figure 1 and Figure 2
respectively, show that the equilibrium experimental data used for an extractant concentration of 12
% has a relatively good fit of the linear regression analysis. This supports the extraction concentration
of 12 % as the best choice.
11
5 Conclusions and Recommendations
After evaluating the equilibrium curves, regression models, percentage of copper and iron extracted
as well as the selectivity towards copper it was concluded that the extractant concentration best
suited to this procedure was the 12% concentration. The other equilibrium curves and regression
models of the remaining extractant concentrations had a poor fit and were not suited to this
procedure. Furthermore, it was found that the 8 % and 16 % extractant concentrations had the
greatest uncertainty after evaluating the triplicate experimental data points. The percentage of
copper (II) extracted as well as the selectivity using the 12 % extractant concentration was the highest.
Recommendations for this practical would be that a longer period than 10 minutes be set out for
equilibrium to be reached so that better separation and extraction can occur.
6 References
Smith, D. & Adams, F. (2022, July 2). Solvent Extraction: Procedures and Applications. Retrieved from
PSIBERG: https://psiberg.com/solvent-extraction/
Grimwade, F . (2012, March 11). What is ICP Spectroscopy? Retrieved from XRF Scientific:
https://www.xrfscientific.com/what-is-icp-spectroscopy/
Chen, H. & Wang, L. (2017, March 2). Solvent Extraction. Retrieved from Science Direct:
https://www.sciencedirect.com/topics/engineering/solventextraction#:~:text=Solvent%20extraction%20is%20the%20process,(or%20slightly%20soluble
)%20solvents.
Baird, M, H, I. (2016, May 16). Solvent Extraction. Retrieved from Science Direct:
https://www.sciencedirect.com/topics/engineering/solventextraction#:~:text=Solvent%20extraction%20is%20the%20process,(or%20slightly%20soluble
)%20solvents.
Davenport, W, G. (2001, February 2). Pregnant Leach Solution. Retrieved from Science Direct:
https://www.sciencedirect.com/topics/engineering/pregnant-leach-solution
12
Appendix A. Experimental Results
Raw data for Copper(ll) and Iron(lll) obtained from ICP analysis
Table 5: Concentrations of copper(ll) and iron(lll) in the aqueous layer for different O/A ratios and
their averages.
G7
G12
G11
Ratios
01:02
01:02
01:02
01:01
01:03
01:04
02:01
03:01
04:01
PLS 1
PLS 2
PLS 3
04:01
03:01
02:01
01:01
01:02
01:03
01:04
01:04
01:04
PLS 1
PLS 2
PLS 3
04:01
03:01
02:01
01:01
01:02
01:02
01:02
01:03
01:04
PLS 1
PLS 2
Cu 324,752
Cu 327,393
(mg/L)
(mg/L)
140.877
140.638
107.765
108.013
146.067
145.969
77.417
77.294
191.85
190.68
175.39
174.4
54.102
54.09
27.054
26.875
25.617
25.459
205.29
205.06
126.589
127.157
146.593
146.63
25.911
25.701
30.695
30.456
48.486
48.374
92.84
92.886
83.624
83.469
182.01
180.89
110.26
110.507
110.2
110.612
88.424
88.315
55.942
55.837
65.257
65.013
68.042
67.824
16.035
15.93
10.979
10.875
19.156
19.106
52.858
52.818
90.813
90.907
98.045
98.12
98.242
98.382
108.807
109.287
118.691
119.28
71.02
70.63
147.654
147.512
Average
Cu
140.7575
107.889
146.018
77.3555
191.265
174.895
54.096
26.9645
25.538
205.175
126.873
146.6115
25.806
30.5755
48.43
92.863
83.5465
181.45
110.3835
110.406
88.3695
55.8895
65.135
67.933
15.9825
10.927
19.131
52.838
90.86
98.0825
98.312
109.047
118.9855
70.825
147.583
13
Fe 259,939
Fe 239,562
Fe 238,204
(mg/L)
(mg/L)
(mg/L)
59.441
59.359
59.151
45.28
45.177
45.049
60.008
59.925
59.771
42.716
42.726
42.66
69.168
69.114
69.011
58.834
58.773
58.643
62.834
62.768
63.038
63.206
63.293
63.626
62.506
62.678
62.862
62.234
62.279
62.082
38.165
38.15
38.006
43.836
43.826
43.653
20.059
20.058
20.012
31.675
31.689
31.674
39.601
39.666
39.778
54.672
55.001
54.813
34.683
34.813
34.636
73.357
73.917
73.795
43.027
43.208
43.212
45.136
45.312
45.336
35.291
35.397
35.314
17.187
17.15
17.131
20.385
20.37
20.338
21.417
21.492
21.367
45.831
45.667
46.079
46.948
46.946
47.051
47.68
46.904
47.916
48.808
49.055
49.288
48.134
48.393
48.231
52.482
52.69
52.577
52.24
52.507
52.296
49.103
49.236
49.192
49.812
50.03
50.046
22.186
22.161
22.151
46.021
46.026
45.839
Average
Fe
59.317
45.168667
59.901333
42.700667
69.097667
58.75
62.88
63.375
62.682
62.198333
38.107
43.771667
20.043
31.679333
39.681667
54.828667
34.710667
73.689667
43.149
45.261333
35.334
17.156
20.364333
21.425333
45.859
46.981667
47.5
49.050333
48.252667
52.583
52.347667
49.177
49.962667
22.166
45.962
PLS 3
167.28
166.31
166.795
14
50.573
50.688
50.36
50.540333
Appendix B. Processed Data
Equilibrium curve data
Table 6: Concentration of organic phase for copper and iron at an extractant percentage of 8%
Organic phase
concentration
Cu
Fe
1.935104
1.070859426
1.936828
1.071703927
1.934828
1.070824548
1.453822
0.803888429
2.898682
1.605413442
2.89997
1.606339905
0.969825
0.535323377
0.970536
0.535308604
0.72793
0.401496965
Table 7: Concentration of organic phase for copper and iron at an extractant percentage of 12%
Cu
0.727925
0.970441
0.969973
1.453212
1.938104
2.899454
1.936697
2.905043
2.906777
Fe
0.402451
0.536255
0.536016
0.803345
1.072328
1.605002
1.607737
1.607548
1.608436
Table 8: Concentration of organic phase for copper and iron respectively at an extractant percentage
of 16%
Cu
0.728118
0.970957
0.970742
1.454786
1.937721
2.906013
1.93733
2.90515
Fe
0.401874
0.535798
0.535782
0.803604
1.07152
1.071261
1.071275
1.607197
15
2.904368 1.607127
Table 9: Concentration of aqueous phase for copper and iron respectively at an extractant
percentage of 8%
Cu
0.003692
0.00283
0.003829
0.003043
0.005016
0.00344
0.002837
0.000707
0.002009
Fe
0.00177
0.001348
0.001788
0.001912
0.002062
0.001315
0.003753
0.001891
0.005612
Table 10: Concentration of aqueous phase for copper and iron respectively at an extractant
percentage of 12%
Cu
0.001257
0.00086
0.001003
0.002079
0.002383
0.002572
0.002578
0.00286
0.00234
Fe
0.004106
0.004206
0.002835
0.002196
0.00144
0.001569
0.001562
0.001468
0.001118
Table 11: Concentration of aqueous phase for copper and iron respectively at an extractant
percentage of 16%
Cu
0.00203
0.002406
0.00254
0.003653
0.002191
0.004759
0.002171
0.002172
0.001738
Fe
0.001795
0.002836
0.002369
0.002455
0.001036
0.002199
0.000966
0.001013
0.000791
16
Regression data
Table 12: Keq values for copper and iron respectively at an extraction percentage of 8 %
Cu
Fe
2.03E+02
1.12E+02
2.03E+02
1.12E+02
2.03E+02
1.12E+02
1.53E+02
8.44E+01
3.04E+02
1.68E+02
3.04E+02
1.69E+02
1.02E+02
5.62E+01
1.02E+02
5.62E+01
7.64E+01
4.21E+01
Table 13: Keq values for copper and iron respectively at an extraction percentage of 12 %
Cu
Fe
3.40E+01
1.87E+01
4.53E+01
2.50E+01
4.53E+01
2.50E+01
6.79E+01
3.75E+01
9.04E+01
5.00E+01
1.36E+02
5.00E+01
9.04E+01
5.00E+01
1.36E+02
7.50E+01
1.35E+02
7.50E+01
Table 14: Keq values for copper and iron respectively at an extraction percentage of 16 %
Cu
Fe
1.91E+01
1.06E+01
2.55E+01
1.41E+01
2.55E+01
1.41E+01
3.81E+01
2.11E+01
5.09E+01
2.81E+01
7.61E+01
4.21E+01
5.08E+01
4.22E+01
7.62E+01
4.22E+01
7.63E+01
4.22E+01
17
Appendix C.
Typical Calculations
Aqueous solution (PLS):
m(Cu2+) = 14.55g ×
63.55
249.68
= 3.703 g
𝑛(𝐶𝑢2 +) = 0.0582746 𝑚𝑜𝑙
𝑛(𝐹𝑒3 +) = 0.08058
𝑚𝑜𝑙
× 0.4𝑑𝑚3 = 0.032232𝑚𝑜𝑙
𝑑𝑚3
Aqueous phase:
[𝐶𝑢2 +] = 140.7575
𝑚𝑔 1 × 10−3 𝑔
×
= 0.1407575𝑔/𝐿
𝐿
𝑚𝑔
𝑚(𝐶𝑢2+) = 0.1407575 𝑔/𝐿 × 0.1 𝐿 = 0.01407575 𝑔
𝑛(𝐶𝑢2+) =
𝑚(𝐶𝑢2+)
= 2.2149 × 10−4 𝑚𝑜𝑙
63.55
Same procedure for Fe3+
Mole Balance:
𝑛𝑜𝑟𝑔 = 𝑛𝑃𝐿𝑆 − 𝑛𝑎𝑞
𝑛𝑜𝑟𝑔 (𝐶𝑢2+) = 0.0582746 𝑚𝑜𝑙 − 2.2149 × 10−4 𝑚𝑜𝑙 = 0.05805311 𝑚𝑜𝑙
Convert back to concentration using ratios of volumes given:
𝐶 =
[Cu2+] = 0.05805311 mol/ 0.03 L = 1.935 M
18
𝑛
𝑉
19
20