Sodium is the 11th Element. It has a similar characteristic to Lithium, the element just above it in the periodic table in that it has just one primary spectral color.

Sodium

Angstrom	Nanometer (rounded)	Color	Hertz	Note	Hertz
5889.95	589	Yellow orange	231.46	A#3	233.08
5895.92	590	Yellow orange	231.23

Violin:

Sine: