In most cases distilled water is used as a blank. That blank also serves as a reference solution. When you are going to measure a sample deviation of the blank indicates the prescence of certain components ( at given wavelengths).  If there were no controls you would not know what to refer to.

In most cases distilled water is used as a blank. That blank also serves as a reference solution. When you are going to measure a sample deviation of the blank indicates the prescence of certain components ( at given wavelengths).  If there were no controls you would not know what to refer to.

Distilled water is used as a control because its purified. Its devoid of contaminants. Controls are needed so you can see what the results would be of an experiment... Positive controls tell you what the positive result of your unknown would be, and negative controls show you what the negative result of your unknown would … Read more

In most cases distilled water is used as a blank. That blank also serves as a reference solution. When you are going to measure a sample deviation of the blank indicates the prescence of certain components ( at given wavelengths).  If there were no controls you would not know what to refer to.

In most cases distilled water is used as a blank. That blank also serves as a reference solution. When you are going to measure a sample deviation of the blank indicates the prescence of certain components ( at given wavelengths).  If there were no controls you would not know what to refer to.