D! It’s a pure substance and a compound
        
             
        
        
        
Atomic Number for neon is 10 
        
             
        
        
        
It is stored in the bonds between atoms.
        
             
        
        
        
It  respresents the higher energy level than 627nm . 
<h3>What is a emission line ? </h3>
Emission lines are the glowing hot gas emits lines of light whereas absorption line  refers to the tendency of  cool atmospheric gas to absorb the same line of light.Some lights produce dark band when the light passes through gas in the atmosphere . There are two line spectrum  and absorption. 
  spectrum is an excitement of  electrons from lower to higher energy levels and when it comes back it releases energy in the terms of colourful lights . 
It represents the  higher energy levels than 627nm because Energy is inversly proportional to wavelength . 
to learn more about Emission lines click here 
  brainly.com/question/28184999
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