How do you address instrumental drift in measurements?

Instrumental drift in measurements is addressed through regular calibration and use of control samples.

Instrumental drift refers to the gradual change in the readings of an instrument over time, which can lead to inaccurate measurements. This is a common issue in many scientific fields, including chemistry, where precise measurements are crucial. To address this, regular calibration of the instrument is necessary. Calibration is the process of adjusting an instrument to ensure its readings are accurate. This is typically done by comparing the instrument's readings with a known standard. For example, a pH meter might be calibrated using solutions with known pH values.

In addition to calibration, the use of control samples can also help address instrumental drift. Control samples are samples with known properties that are measured alongside the samples of interest. By comparing the readings from the control samples with their known properties, any drift in the instrument's readings can be detected and corrected for. For example, in a spectrophotometric analysis, a blank sample (a sample that should not absorb any light at the wavelength of interest) might be measured regularly to check for any drift in the instrument's baseline.

Another method to address instrumental drift is through the use of internal standards. An internal standard is a substance with known properties that is added to all samples, including the control samples. The instrument's response to the internal standard can then be used to correct the readings from the samples. This can be particularly useful when the drift is not constant but varies in a predictable way.

In conclusion, addressing instrumental drift is crucial for obtaining accurate measurements in chemistry. Regular calibration, the use of control samples, and the use of internal standards are all effective methods for dealing with this issue.