Change in state(from liquid to solid) and change in colour I believe.
it's def. TRUE. i got the same question and i got it right
<span>This spectrometer reading shows some red, blue, and purple. Our atom is most likely Hydrogen source.
This spectrometer reading shows some reds, orange, and yellow. Our atom is most likely Neon source.
This spectrometer reading shows some red, yellow, and blue. Our atom is most likely Helium source.
This spectrometer reading shows some yellow, blue, and purple. Our atom is most likely Mercury source</span>
