Pre-Lab Questions - Bohr Atom and Emission Spectroscopy

Line spectra

Contains only discrete wavelengths, or "lines" with dark regions in between. An example of this is that different elements would emit line spectra when excited either thermally or electrically. The light emission only at specific wavelengths.

Explain the difference between emission and absorption of energy.

The difference between emission and absorption of energy are that emissions of energy represents the transition of electrons to a lower energy level. Absorption of energy represents the transition of electrons to a higher energy level.

Quantized

The energy levels for the orbits can only have specified energies that vary in a step-like fashion. An example of this is that the energy levels of electrons in atoms are quantized. The electron's energy can have only certain values, and all intermediate values are prohibited. Electrons can only exist at specific energy levels, separated by specific intervals.

Continuous spectra

The intensity of light varies smoothly as a function of wavelength. An example is sunlight. When passed through a prism, sunlight is dispersed into a continuous band of colors of relatively equal intensity. When light emitted from a solid substance passes through a prism, it produces a continuous spectrum of colors.

Transition

The movement of an electron from one energy level to the other. An example of this is that electrons can move to higher energy levels as a result of thermal or electric excitation.

Using the Bohr model, calculate the energy associated with the transition from n = 4 to n = 1 (in kJ/mol). ΔE (kJ/mol) =

ΔE (kJ/mol) = -1230 kj/mol

Using the energy of transition described in question 2, what is the wavelength of the light (in nm) emitted? λ (nm) =

λ (nm) = 97.2 nm