Procedure for setting up PASCO Probes :
Materials :
Wireless pH probe,
Ring Stand
DI Water bottle
250 mL beaker
50 mL beaker
pH Probe use:
1. Turn on the pH sensor.
2.Open the SparkVue App. ( Or get it as a web-browser app on the PASCO web site)
3.Click on the middle icon, Sensor Data
4. The pH meter should be recognized and listed. BE SURE TO PICK YOUR sensor. There is a number on the sensor that will be listed on the screen.
5. On the computer, open the appropriate graph set up as instructed. The standard set up is one with a data table and a line graph.
6. Set up the data table and graph. Fill in the titles and label the axis if needed...it may appear automatically.
Some tips : Time goes on the "X-axis" . Titles put the X-axis first, so, "Time vs pH"
The first column of the data table should be the X-axis.
Additional columns can be added by clicking on the icon in the lower left corner. Use this with part D , to show data for two probes.
7 . START Measuring: Fill a 50 mL beaker with 30 mL of D.I. water. Remove the cover from the pH probe.
Suspend the pH probe in the water using a ring stand and clamp..
Click on the start button at the bottom of the screen , and a continuous data stream is run.... Do this for30 seconds, and stop. You should have some data and a graph generated. Since nothing was done to change the pH , the graph should be a horizontal line. If it is not, try a different graph view.
Also, if the pH is not near 7.0, then you need to calibrate the probe. Ask for help on this.
Calibration : Calibration is done in a 50 mL beaker. You need to conserve the Buffer solution. You need just enough buffer to cover the bulb at the end of the pH meter. Wireless: Click on the screw driver icon.
In the upper right, click on the target icon, next to pH.
Click on the 2 point as calibration type. Hit continue. Enter the Cal Point one as 10.0 and use 20-30 mL of the pH 10.0 buffer in the 50 mL beaker,
Empty the buffer and rinse with DI Water.
Then 4.0 for the cal. pt. 2. St calibration and "OK".
7. NEXT , do it again. This will be Run 2. Click the start button.
Run 2 : Run it for two minutes and stop. Check that this graph and data have been saved. How can this data and graph be transferred to a google doc, or your Google folder? Experiment with doing this. Record how you achieved it.
8. EXPERIMENTAL RUN 3 : Now you will test the pH. Get a dropper bottle with 0.1 M HCl. Use the beaker of water ( 50 mL Beaker) Add 20 ml of D.I. water. START recording . Add Two drops of HCl every 5 seconds ( approximate). Continue until the pH has changed to approximately pH 2 . STOP recording when the pH reaches 2.8 . Be patient, this may take up to ten minutes . Use a glass stirring rod and gently stir. Avoid hitting the pH probe.
9. SAVE your file with your name and date and pH Part A. Create a folder in your shared Google Folder with the title , " PASCO ENZYME LAB". Try to transfer the data table and graph. Remember, labels are very important.
One Document per Team is needed