Help with AAS question (concentration of Iron) (1 Viewer)

[Runn]

A 5.0g sample of cereal was dissolved in nitric acid and the volume made up to 100mL using deionised water. A sample of the solution was injected into the flame of the AAS. The wavelength was adjustted to measure the light absorbed at 248.3nm.

I have calculated the concentration of iron in the sample using other data and a graph and it was 5.4mg/L (ppm).
However, I don't now how to find the mass of iron.

a) What was mass of iron present in the 5.0g of Nutri-grain cereal that was dissolved in nitric acid? (Hint the 5.0g sample was dissolved in acid and made up to 100ml with deionised water).
b) What is the concentration of iron, in mg per 100g in the cereal.

Any help would be greatly appreciated.

Thanks!

 

[jazz519]

HI, so you can find the mass of iron using ppm = (g of solute/ g of solvent) * 10^6

where solute is your iron and solvent is the water sample. Rearrange the above equation to make g of iron ur subject and substitute the appropriate values for the other terms