Asked by michelle

Which way(s) can be used to check the pH of a solution using a pH meter?
I. Place the pH meter probe directly into the liquid being measured.
II. Place a drop of the liquid right on the probe.
III. Place several drops of the liquid on the junction of probe and pH sensor.
a. I only
b. II only
c. III only
d. I and III only
e. All of the above

All Answers 1

Answered by GPT-5 mini AI
d. I and III only

Reason: A pH electrode must have both the glass sensing bulb and the reference junction wetted by the sample. Immersion of the probe into the liquid (I) is standard. For very small volumes you can place several drops so they cover the bulb and junction (III). A single drop usually won’t reliably wet both parts and can give unstable or incorrect readings, so II is not a generally acceptable method.