Question

a) Which one of the following statements was assumed by Bohr in developing his atomic theory?

-A) Photons have momentum

-B) There are stationary states in which the electron does not radiate energy

-C) Emission line spectra are a result of photons jumping from lower to higher energy levels

b) When observing an absorption line spectrum of a cool gas, some electrons in the atoms of the gas are believed to:

-A)Move from higher to lower energy level

-B)Move from lower to higher energy level

-C)Combine in chemical reaction

-D)Jump from one atom to another

c) Calculate the wavelength of an electron accelerated from rest through a potential difference of 1.00x10^3V

Answer 1

a) c) Emission line spectra are a result of photons jumping from lower to higher energy levels.

Electromagnetic radiation (such as light) is emitted from an atom only when an electron moves from one energy level to a lower level. According to “classical” physics theory (before quantum mechanics), radiation should be emitted continuously by an orbiting electron.

b) b) moves from lower level to higher level.

Because absorption spectra occurs when an atom absorbs light of a particular wavelength and it is missing in the spectra called absorption spectra.