Use of Blank Solutions

Use of Blank Solutions

Section 1: Understanding Blank Solutions

  • Blank Solution: A solution that does not contain the substance of interest, but has all other components which can also contribute to the overall measurable signal.
  • Purpose is to calibrate the instrument and set a baseline reading against all other variables in the experiment.
  • Commonly used in analytical chemistry techniques such as spectrophotometry, chromatography, and fluorimetry.

Section 2: Preparation of Blank Solutions

  • Prepared with the same procedure as the actual sample but skipping the addition of analyte or target component.
  • Contains all possible elements that could cause absorption or interference, except the substance to be measured.
  • Sample matrix needs to be the same as the sample solution.

Section 3: Importance and Use of Blank Solutions

  • Blank solution is used as a zero reference point in many analytical techniques.
  • Helps in eliminating effects caused by background noise or environmental factors, enhancing the accuracy of results.
  • It also helps in correction of systematic errors in the measurement system.
  • In techniques like spectrophotometry, a blank is run first to set the instrument to zero absorbance.

Section 4: Types of Blank Solutions

  • Method Blank: Prepared alongside the sample using the same method to measure any contamination that may occur during the sample preparation.
  • Field Blank: Used to check contamination during field sampling process.
  • Instrument Blank: Used to flush the instrument and rule out any possible interfering signals in the device.