Each line in the spectra represents the energy 1.) absorbed as an atom loses an electron
2.) released as an electron moves from a lower energy state to a higher energy state
3.) released as an electron moves from a higher energy state to a lower energy state
4.) absorbed as an atom gains an electron

answer: option (a) is the correct answer.

explanation:

the measurement of hydrogen ions in a solution is known as ph.

if ph of a solution is less than 7 then the solution is acidic. if ph of a solution is greater than 7 then the solution is basic.

when the ph of a solution equals 7, then the solution is considered as neutral.

the ph of pure water is 7, therefore, it means that concentration of hydronium ions equals that of hydroxide ions.