Atomic absorption spectroscopy was used to determine the amount of aluminum in a sample of sunscreen. A blank solution was measu
red seven times to determine the detection and quantitation limits of the spectrometer. The blank readings were: 0.0159 , 0.0081 , 0.0095 , 0.0109 , 0.0090 , 0.0114 , and 0.0090 AU. Determine the signal at the detection limit and the signal at the limit of quantitation for this method.
Detection limit (LOD) is defined as the lowest signal which, with a stated probability, can be distinguished from a suitable blank signal. In the same way, quantification limit (LOQ) is defined as the lowest analyte concentration that can be quantitatively detected with a stated accuracy and precision.
There are many formulas but the most used are:
LOD = X + 3σ
LOQ = X + 10σ
Where X is average and σ is standard desvation
For the blanks readings the average X is 0,0105 and σ is 0,0024
The answer is the elements in a periodic table. <span>On the basis of the elements in the periodic table, they are divided into metals and non metals. </span>
I believe the correct answer from the choices listed above is option B. A chemical formula written above or below the yield sign indicates <span>that the substance is used as a catalyst. I am certain with this answer. Hope this helps. Have a nice day.</span>