A pH meter is an example of which testing method?Group of answer choicesDirection reading probeLight refraction deviceColorimetric paper

To determine the correct answer to the question regarding what type of testing method a pH meter represents, let’s analyze the options provided:

1. Direct reading probe: A pH meter uses a glass electrode as a probe that directly measures the hydrogen ion concentration in a solution. This allows for an instant readout of the pH value.

2. Light refraction device: This method generally involves measuring the angle of light refraction through a solution. It is not applicable to pH measurement.

3. Colorimetric paper: This method involves comparing color changes in a chemically treated paper to estimate pH but is not how a pH meter operates.

Conclusion

Based on this analysis, a pH meter is best classified as a Direct reading probe testing method.