CHEMICAL TESTING

test tubes

Testing the water quality is essential in determining the health of an aquatic ecosystem. We will perform the following tests: Dissolved oxygen (DO), pH, Water temperature, turbidity, nitrates, nitrites, phosphate, and coliform.

For all water tests performed in class we will use the LaMotte test kits, or the Pure Water test kits. This page will illustrate how and why we do these tests. Once you have read through the page, you can click on the link for activity #1 to try chemical testing for yourself!!

 

pH Test

Follow the directions on the LaMotte test kit to determine the pH of the water sample. Compare the color on the test strip with the colors on the chart in the LaMotte guide, or the PureTest guide. Once you have a number, compare your number with the pH scale below to determine the pH quality of the water. Record the pH in the data table.

 

Water Temperature:

 
water temp Water Temperature: Take a sample of water from the buckets and insert a thermometer. Record the temperature in degrees Celsius as well as degrees Fahrenheit.

 

Dissolved Oxygen Test:  
do test Follow the directions in the LaMotte test kit for dissolved oxygen. Once the tablets have dissolved, compare the color of the vial with the colors on the chart to determine how much dissolved oxygen is in our sample. Record your data in the data table.

 

Coliform test;  
coliforms Follow the directions in the LaMotte test kit. Remember, this vial must remain undisturbed on the lab counter for 48 hours. Then compare results indicated on the LaMotte card to determine if there are coliforms present in the water. Record your data.

 

Nitrates, Nitrites, and Phosphate test:  
nitrates The Nitrates, Nitrites, and Phosphate tests are all on the same test strip in the PureWater test kit. Fill the vial to the fill line with water from the stream sample. Dip the test strip in the water and swirl 3 times. Wait one minute, then compare the colors on the test strip with the colors on the PureWater test card. Record your results in the data table.

Now that you now how to perform the chemical tests, you will do so yourself. If there are stream water samples in the room, follow directions from Mrs. Bicher. If there are no samples available, we will be using the virtual samples..so on the left side of the screen, click on the link that says Water Chemistry lesson #1. Have fun!