[Dolphinsiu]

We use flameless atomic absorption to trace the aluminium content in this drink.

I get stuck when I meet the following questions:

1.Which is the more accurate method of obtaining a calibration curve, using peak height or peak area? Explain

My attempted answers:
Peak area due to self absorption at high concentration detemines the constant peak height.

2. Find out what kind of chemical interaction would occur inside an aluminium soft-drink can, and the method used to prevent chemical interaction between beverages and aluminium.

My attempted answers:
2Al + 6H+ --> 2Al3+ + 3H2
To pump more hydrogen gas inside the can.

3. Why nitric acid has to be added to the soft-drink samples?

My attempted answer:
2H+ + CO32- --> CO2 + H2O
To shift the above eqm to the right and increase CO2 evolution.

4. Why should we de-gas or remove the carbon dioxide before measuring the content of trace aluminium in beverages?

My attempted answer:
To prevent gas bubbles that cause error in abosrbance.

5. Why was a flow of argon gas maintained around the atomizer in the analysis?

I cannot the answer this question!

I hope you can help me answer a few questions in above! Thank you!