Question

You aren't sure whether or not your ph meter needs to be calibrated, so you put it in a solution that you know has a ph of 7. You take four separate readings, which are reported as 5.5, 8.6, 7.2, and 9.4. What can you conclude about the calibration of your ph meter?

1) The ph meter is calibrated correctly
2) The ph meter is not calibrated correctly
3) The ph meter is partially calibrated
4) Cannot be determined from the given information

Answer 1

The pH meter is not calibrated correctly.

Step-by-step explanation:

The readings of 5.5, 8.6, 7.2, and 9.4 indicate that the pH meter is not calibrated correctly. Ideally, when measuring the pH of a solution with a known pH of 7, the readings should be close to 7. However, the readings obtained are significantly different from 7, suggesting that the pH meter needs calibration.