If wavelength of an element isn't marked on wavelength of mixture, it means that this element isn't part of it. I also attached picture to make it more clear I hope you will understand it, and oh btw the answer is element X (answer number 3)
The question deals with the **emission spectra **of elements, which are unique patterns created when energized atoms emit light. This concept is key to identifying elements in a mixture by comparing the combined emission spectrum to individual spectra of known elements. ;
To determine which elements are in a mixture based on their bright-line spectra, compare the lines in the spectra of individual elements with those in the mixture. If any lines of an element are absent in the mixture spectrum, that element is not included in the mixture. This method allows you to identify which elements are present accurately.
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