coefficient: they balance the chemical equation you have to make sure the number is as small as it can. It is also used to convert different compounds to compounds or quantities to quantities.
Answer is: (4) emits energy as it moves to a lower energy state.
Atom emits a characteristic set of discrete wavelengths, according to its electronic energy levels.
Emission spectrum of a chemical element is the spectrum of frequencies emitted due to an atom making a transition from a high energy state to a lower energy state.
Each transition has a specific energy difference.
Each element's emission spectrum is unique.
Answer: It is called a Crookes Tube, and he used it to discover cathode rays, which were later determined to be electrons.
Because water vapor, uncontained, will diffuse out into the atmosphere and is not close enough to condense back into the liquid water, so no equilib. can be established.
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