Rutherford experiment

Click Coached Problems for a self-study module on the Rutherford experiment. 

Similar to Black, Daniel Rutherford (1749-1819) studied gases for his medical degree dissertation. Rutherford found that common air contained a part that supported respiration and a part that did not. Initially, Rutherford assumed the part that did not support respiration was contaminated by fixed air. Rutherford experimented and removed the fixed air, and he discovered the uncontaminated air still did not support life or combustion. Rutherford assumed the gas he had isolated was ordinary air saturated with phlogiston hence, it was phlogisticated air, which he referred to as noxious air. What Rutherford had isolated was nitrogen, and he is given credit for its discovery. 

In Rutherfords experiment, shown in Figure 3.16, a beam of positively charged particles, called alpha particles, was directed through an ultrathin sheet of gold foil. Since alpha particles were known to be thousands of times more massive than electrons, it was expected that the alpha-particle stream would not be impeded as it passed through the atomic pudding of gold foil. This was indeed observed to be the case—for the most part. 

The Rutherford Experiment movie (eChapter 2.4) shows alpha particles impinging on a thin gold foil. Describe what happens to the alpha particles and discuss how the results of this experiment shaped the modern view of atomic structure. 

Hg. 3.1 Explanation of the Rutherford experiment. The path of the alpha particles Is shown by arrows. Only If an alpha particle makes a direct hit on a nucleus does It suffer a large deflection. 

FIG. 23. Rutherford experiment led to concept of nucleus and opened the door to modern nuclear physics. Alpha particles emitted from radioactive source were deflected when passing through gold foil. Amount of deflection was recorded when particles struck the photographic plate. 

The possibilities of Doppler-free two-photon spectroscopy for metrology and fundamental physics has been impressively demonstrated by precision measurements of the 1S-2S transition in atomic hydrogen [260-263]. Precise measurements of this one-photon forbidden transition with a very narrow natural linewidth of 1.3 Hz yield accurate values of fundamental constants and can provide stringent tests of quantum electrodynamic theory (Sect. 9.7). A comparison of the 1S-2S transition frequency with the 2S-3P frequency allows the precise determination of the Lamb shift of the 15 ground state [261], whereas the 2S Lamb shift was already measured long ago by the famous Lamb-Rutherford experiments where the RF transition between 25 1/2 and 2P /2 were observed. Because of the isotope shift the 15-25 transitions of and differ by... 

Mary V. Lorenz, "Bowiing Baiis and Beads A Concrete Anaiogy to the Rutherford Experiment," ]. Chem. Educ.,Vo. 65, 1988,1082. 

Prior to Rutherford s gold-foil experiment, the mass and positively charged particles of an atom were thought to be evenly distributed throughout the volume of the atom, (a) Watch the movie of the Rutherford Experiment (eChapter 2.2), and describe how the experimental results would have been different if the earlier model had been correct, (b) What specific feature of the modern view of atomic structure was illuminated by Rutherford s experiment ... 

Describe the Rutherford experiment, and explain why the observations indicate that most of the mass of an atom is concentrated in a very small particle, the nucleus. 

Co to http //now.brookscole.com/ cracoliceJe and click Coached Problems for an exercise on The Rutherford Experiment. 

The Rutherford experiment was performed and its conclusions reached before protons and neutrons were discovered. When they were found, why was it believed that they were in the nucleus... 

Rutherfords experiment and the nucleus-shell-structure of the atom Radio activity... 

Charges and their behaviour Rutherfords experiment in a shoe box Rutherfords experiment The relation between nucleus and atom Diff. The life of E. Rutherford... 

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