What color would Nickel ions burn (say in a compound of NiSO4)? Green? If you searched this on the web please post the link for a reference I can use.

I don't have a reference. In fact, it is not listed in any text book I own and it is not listed on
any of the sites I found on the web. What I wrote to you earlier is the result of personal experience; I performed many flame tests during my career as a chemist. The part about not being reliable is also from personal experience. I have a book at home that lists ALL the lines from ALL the elements. Nickel has no strong lines above about 350 nm and the eye is not sensitive to that wavelength, anyway. The most comprehensive flame test site I found on the web is below but that doesn't list Ni either. In fact, almost all flame tests are carried out with nichrome wire (an alloy of Ni and Cr) or Pt. Given the cost of Pt, you can guess which wire is used the most often. The chloride gave me better results than other salts. I don't have specific recollections of using NiSO4.
For some reason I can't post the site on this round. I will send this, then another containing the site. I'm sorry I can't be of more help.


why does a clean new nichrome wire produce an orange light when heated in a flame, even though there is no test compound on the wire

When a clean new nichrome wire is heated in a flame, it produces an orange light due to the presence of chromium in the alloy. Nichrome wire is made up of a combination of nickel and chromium. When heated, the chromium atoms emit energy in the form of light. Different elements have different energy levels and electron configurations, which determine the color of light they emit when heated. In the case of chromium, it emits light in the orange region of the electromagnetic spectrum. Therefore, when the nichrome wire is heated, it produces an orange light.

The specific reasons for this color are related to the electronic transitions happening within the chromium atoms when heated. When the heat energy is applied to the wire, the electrons in the chromium atoms get excited and move to higher energy levels. As they return to their original energy levels, they release energy in the form of light. The wavelength of this emitted light corresponds to the orange region of the spectrum.

It is important to note that this orange color is specific to the presence of chromium in the nichrome wire. If you were to use a different alloy or metal wire, the color of light emitted when heated would be different.