Identication of Contaminants In Water

[Grove1996]

The purpose:
Basically I've been given a pre-contaminated sample of water, as well as a post-contaminated sample of water. I have to determine what the water is contaminated with, and the concentration of the contaminants present in the water.

My Problem:
I have determined one contaminant that is present in the water, and this is ammonium with a reading of approximately 430 mg/L. However, it's not just ammonium by itself, there are other contaminants present. I've tested for a few things (calcium/chloride/nitrate) and all is fine. I'm limiting it down to phosphate or sulfate. The pH of the water is 8, and I know that ammonium in water creates a more basic solution. So whatever the other contaminant is, I'm assuming there is not much of it. Since I'm in high school the testing equipment I can use is very limited. I can test for phosphate but I am yet to find a procedure I can use to test for sulfate ions.

Does anyone know a procedure I could use to determine the amount of sulfate ions present in a given sample of water. I've searched long and hard and unable to find anything I can do with the equipment I have at school.

Thankyou

 

[Borek]

The most obvious approach is the precipitation of barium sulfate.

 

[Grove1996]

The most obvious approach is the precipitation of barium sulfate.

I've research this a little bit. From my understanding it only can determine whether there is sulfate present in the water sample, but not the concentration.

 

[Borek]

No, it can be used for quantitative analysis as well, this is one of the most basic gravimetric methods.

 

[DeeNos]

I understand the importance of identifying and quantifying contaminants in water. Based on the information provided, it seems that the water sample in question is contaminated with ammonium, and there may also be other contaminants present, possibly phosphate or sulfate.

To accurately determine the concentration of sulfate ions in the water sample, I would recommend using a spectrophotometric method. This method involves using a spectrophotometer, which measures the amount of light absorbed by a sample, to detect the presence and concentration of sulfate ions. A colorimetric test could also be used, which involves adding a reagent that produces a color change in the presence of sulfate ions.

However, since you mentioned that your testing equipment is limited, another option could be to use an ion-selective electrode (ISE) to measure sulfate ions. This method involves using an electrode specifically designed to detect and measure the concentration of a specific ion in a solution.

It is important to note that the accuracy and reliability of these methods may vary depending on the quality and calibration of the equipment used. Therefore, it would be beneficial to consult with a science teacher or a professional laboratory to ensure the accuracy of your results.

Overall, identifying and quantifying contaminants in water is crucial for ensuring the safety and quality of our water supply. I hope this information helps you in your research and analysis.