It can be a compound or a single element. An element is a pure substance that cannot be separated into simpler substances by chemical or physical means. There are about 117 elements, but carbon, hydrogen, nitrogen and oxygen are only a few that make up the largest portion of Earth.
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1 . Each color has a different wavelength allowing the eye to see it.2 . The shirt reflects the blue wavelengths.
3 . Charcoal absorbs all wavelengths of light that fall on it4 . Red
5 . Purple 6 . Yellow7 . It contains all of the wavelengths of the visible light spectrum.
A circuit breaker must be replaced after too much current flowing through it causing it to melt.