[pie741]

so I'm doing a lab where i have to identify different chemicals based on the color of the flame. here are samples strontium, sodium, barium, calcium, copper, lithium, potassium. I'm supposed to use the electromagnetic spectrum to list them in order of increasing energy changes. the issue i have is that i can't clearly label each element to a color but i assume this is a common lab and that someone might know the arrangement.