Atomic Hydrogen Lab Report

Chemistry 2500- Exercise C4
The Emission Spectrum of Atomic Hydrogen

Objective The purpose of this lab was to calculate an experimental value for the Rydberg constant and then the ionization energy for the hydrogen atom. These values will be obtained by using a prism spectrograph to measure the wavelength value for a section of the visible line spectrum of atomic hydrogen.

Theoretical Background When H+ combines with an electron it forms it’s excited state, H. This excited atom will release light with a photon of energy as it goes to the lowest possible energy state. The light and photon of energy that are released relate to the difference in energy levels between the ground-state and the excited state. The Rydberg constant
302.0+(16/30)-180=122.53 average angle=122.565

c.)122.0+(14/30)=122.46 303.0+(18/30)-180=123.60 average angle=123.030

d.)122.0+(22/30)=122.73 303.0+(20/30)-180=123.67 average angle=123.200

2.)Finding Angle for Each Emission line of Hydrogen angle+(minutes/30)=final angle 1 angle +(minutes/30)-180=final angle 2 (angle 1+angle 2)/2=average angle a.) 116.0+(15/30)=116.50 296.0+(14/30)-180=296.47 average angle=116.485

b.) 120.0+(30/30)=121.0 300.0+(27/30)-180=120.90 average angle=120.950

c.) 125.0+(30/30)=126.0 305.0+(28/30)-180=125.93 average angle=125.965

3.) Finding Wavelength of Hydrogen Angle=slope(wavelength-2) + intercept
a.) 116.485= -2.697x10-8(wavelength-2) + 131.2 wavelength= 4.27E-05 cm

b.) 120.950= -2.697x10-8(wavelength-2) + 131.2 wavelength= 4.91E-05 cm c.) 125.965= -2.697x10-8(wavelength-2) + 131.2 wavelength= 6.59E-05 cm

4.)Finding Ionization Energy
a.) For ground State n1=1