After field works we went to laboratory to analyze water samples
In this task we analyzed our group's and group 5's water samples. First we took water from samples of the inflow and outflow of Pieni-Valkeinen, inflow of Iso-Valkeinen and groundwater from groundwater well and deionized water as zero sample in cuvettes. Then we pipetted 3 drops of Mineral Stabilizer and Polyvinyl Alcohol Dispersing Agent, and 1 ml of Nessler Reagent in each cuvette. We mixed cuvettes after every reagent. Then we waited 1 minute, and used Hach 2800 spectrophotometer to analyze amount of ammonium nitrogen. Before analyzing samples we reseted spectrophotometer with zero sample.
There are our results:
Group 5
1. 0,23 mg/l NH3-N
2. 0,24 mg/l NH3-N
3. 0,26 mg/l NH3-N
7. 0,07 mg/l NH3-N (groundwater sample)
Group 7
4. 0,20 mg/l NH3-N
5. 0,25 mg/l NH3-N
6. 0,30 mg/l NH3-N
8. 0,57 mg/l NH3-N (groundwater sample)
Results are pretty similar except groundwater samples, our sample was muddy and other groups sample was almost clear.
sample1: 0.012 mg/l
Determination of chemical oxygen
demand in water (COD Mn or KOMN4-number)
1. Take 18 flasks, number 0-8, each number two identical
samples, sample 0 is deionized water each 10ml, 1-8 is 8 samples each 5ml
sample and 5ml deionized water
2. Add 0.5 ml of H2SO4 (4M) and 2 ml of potassium
permanganate to each of the 18 samples.
3. The flask is covered with foil paper (to avoid
evaporating a large amount of sample by heating). After heating in boiling
water for 20 minutes (group 0 is still purple, group 1-8 turns orange) and
cools to room temperature in cold water.
4. Add 1ml of iodinated (yellowing) to the cooled sample.
And 5 drops of potassium iodide (blue)
Add the magnet to the magnetic stirrer and titrate the
sample with sodium thiosulfate until the blue color disappears
Color, nitrate type and opacity determinations
The analyze of the color
We analyzed our group´s and fifth
groups water samples. Firstly, we start by determining the color of the
samples. We used for that the HACH 2800 spectrophotometer, the program number
120. We pipetted 10 ml of ionized water to
one cuvette, which we used for resetting. Then we pipped the water samples to
eight cuves and measured the colors of the samples.
water samples and ionized water (0)
We had to analyze the color twice as
at first try we placed the cuvettes by the wrong way in the spectrophotometer.
We got a good remind that the line needs to be on the right side.
Results of the colors
Group 5
Analyze of the nitrate type
For analyzing the type of nitrate, we
used also the HACH 2800 spectrophotometer, program number 353 and the
wavelength 400 nm. We reset the cuvettes by themselves and did these one by
another. After the reset, we added NitraVer 5 Nitrate reagent powder and placed
parafilm on it to be able to shake it properly for one minute and waited for
five minutes before measuring the result of the nitrate.
The results of the nitrate
Group 5
Group 7
Turbidity determinations
For turbidity determination we
used Turbidmeter HACH 2100N IS. We poured the samples to turbidity cuvettes and
waited until the result stabilize. We wrote down the result by one decimal. Lastly,
we washed all the sample cuves by 10% saline and deionized
water.
The results of turbidity
Group 5
Group 7
Ammonium nitrogen analysis
In this task we analyzed our group's and group 5's water samples. First we took water from samples of the inflow and outflow of Pieni-Valkeinen, inflow of Iso-Valkeinen and groundwater from groundwater well and deionized water as zero sample in cuvettes. Then we pipetted 3 drops of Mineral Stabilizer and Polyvinyl Alcohol Dispersing Agent, and 1 ml of Nessler Reagent in each cuvette. We mixed cuvettes after every reagent. Then we waited 1 minute, and used Hach 2800 spectrophotometer to analyze amount of ammonium nitrogen. Before analyzing samples we reseted spectrophotometer with zero sample.
There are our results:
Group 5
1. 0,23 mg/l NH3-N
2. 0,24 mg/l NH3-N
3. 0,26 mg/l NH3-N
7. 0,07 mg/l NH3-N (groundwater sample)
Group 7
4. 0,20 mg/l NH3-N
5. 0,25 mg/l NH3-N
6. 0,30 mg/l NH3-N
8. 0,57 mg/l NH3-N (groundwater sample)
Results are pretty similar except groundwater samples, our sample was muddy and other groups sample was almost clear.
LCK 349 Phosphate
Today our task was to measure the amount of phospate in our water
samples.
So what we did
step by step:
So after all this
our results were as followed (amount of phosphate):
sample1: 0.012 mg/l
sample2: 0.023
mg/l
sample3: 0.011
mg/l
sample4: 0.008
mg/l
sample5: 0.028
mg/l
sample6: 0.014
mg/l
sample7: 0.028
mg/l
sample8: 0.177
mg/l
Water quality - Determination of suspended solids - Method by filtration
through glass fibre filters
Principle:
Using a vacuum or
pressure filtration apparatus the sample is filtered though a glass fibre
filter. The filter is then dried at 105 C and the mass of the residue retained
on the filter is determined by weighing.
We started this
work by pouring our sample waters from one bottle to another, and between these
two bottles we had fibre filter that catched suspended solids. The ammount of
water we poured were 250 - 300 ml.
After this we
placed the fibre filters to the oven where they were about 30-45mins.
Now we were able
weigh in the filters, and compare their weight to the weight before the
contamination.
This weight
difference between the clear filter and dirty filter told us the amount of
suspended solids in the filter.
Results:
Sample1 25.7 mg/l
Sample2 37.3 mg/l
Sample3 11.5 mg/l
Sample4 45.2 mg/l
Sample5 19.3 mg/l
Sample6 8.1
mg/l
Group
|
Sodium
thiosulfate
|
|
0
|
2.05
|
2.05
|
1
|
1.46
|
1.47
|
2
|
1.49
|
1.48
|
3
|
1.59
|
1.58
|
4
|
1.60
|
1.59
|
5
|
1.49
|
1.50
|
6
|
1.53
|
1.48
|
7
|
1.92
|
1.98
|
8
|
1.87
|
1.85
|
In this test, it was very interesting to see the
different color change process of the entire sample, especially after the
titration of sodium thiosulfate, the solution completely turned white like
water. We found that the clearer the
sample, the less sodium thiosulfate used in the titration. The instruments used in the experiment are
volumetric flasks, titrators, automatic pipettes, etc. These instruments are
very convenient for us to use, and make the experiment faster and more
efficient.
1. 47 PtCo
2. 39 PtCo
3. 34 PtCo
7.
7 PtCo
Group
7
4. 38 PtCo
5. 41 PtCo
6. 42 PtCo
8.
393 PtCo
Ground water sample; reason why the PtCo is
very high.
1. 0,1
2. 0,1
3. 0,1
7. 0,117
4. 0,2
5. 0,1
6. 0,192
8. 0,336
Samples
6 and 7 were under measuring range 0,23-13,50 mg/l NO3 –N.
1. 1,1 NTU
2. 0,9 NTU
3. 0,6 NTU
7.
1,0 NTU
4. 0,7 NTU
5. 1,9 NTU
6. 0,6 NTU
8.
43,0 NTU
Thanks for your blogs! Those were really good :)
ReplyDelete