I want to determine the weight percentage of sodium chloride in a potato chip. I can see from this answer that atomic absorption spectroscopy (AAS) can be used to quantify sodium chloride in a solution. I propose the following measurement scheme:
- Dissolve the potato chip in a sample of water with known mass
- Homogenize the solution until it has a uniform composition
- Draw 10 aliquots from this solution
- Use AAS to measure the weight percentage of salt in each aliquot
- Use the mean and standard deviation of the weight percentages from the 10 aliquots to generate an estimate of the true weight percentage with a confidence interval
1) What is the best way to get the mass of the aliquot that belongs to the potato chip? I want to minimize measurement uncertainty.
2) There could be compounds other than sodium chloride that contains sodium or chloride in a potato chip. I fear that the AAS won't detect sodium chloride, but sodium and chloride ions separately. What is the best way to measure the concentration or mass of sodium chloride with AAS? If AAS is not the best way, can you name an alternative method?