# Ionic emission spectrum contamination

Imagine that I am trying to identify the presence of ions from among the metals $\ce {Li,Na,K,Ca,Sr, Ba}$ in some solution through their emission spectrum.

By mistake the wire used to introduce samples into the flame exciting the ions is contaminated with $\ce{Al(NO3)3}$. The emission energies for Aluminum are $\pu{3.9\times 10^{-19}~J/atom, 3.58\times 10^{-19} ~J/atom, 2.97\times 10^{-19}~ J/atom}$.

How will this mess up the identification of the other ions?

Since $3.58\times 10^{-19}$ matches one of the Ca peaks and $2.97\times 10^{-19}$ matches one of the Sr peaks I imagine I could misleadingly identify these two as being present when they were not?

• I would convert your energies to wavelengths then look up the most accurate wavelengths for the metals you can find thus how different Al is from any of the others. Next look at the wavelength resolution of your instrument to see if you can distinguish them. Second, the pattern of lines may help since if one matches closely the others are likely not to do so. – porphyrin Nov 24 '16 at 10:26