Question

Choose a scientist from the timeline on the previous page. Conduct research using outside sources. Be sure to choose reliable resources such as government, scientific, and educational websites. Document all research in your own words. Be sure to properly cite all resources used in your assignment. Research and respond to the following: Were there experiences in his life that led to his interest in science and the study of the atom? Defend his work on the atom and its contribution to the modern atomic model. Point out which contributions are present in the modern atomic model and which were eventually disproven and thus are not part of the modern model. You may choose how to present your responses. Please make sure to review the grading rubric. You will submit your research to your instructor.

Options:
a. I cannot perform this task
b. I need more information about the scientist
c. I will conduct the research and respond
d. I will not conduct the research

Answer 1

The modern atomic model has evolved through critical discoveries by key scientists such as J.J. Thomson, Ernest Rutherford, Max Planck, Albert Einstein, Niels Bohr, and J.C. Chadwick. Their research led from the discovery of subatomic particles to the quantum mechanical model that describes electron probabilities rather than fixed orbits.

Step-by-step explanation:

The development of the modern atomic model is a fundamental aspect of chemistry that has evolved significantly over time. Several prominent scientists played crucial roles in advancing our understanding of the atom's structure and behavior.

J.J. Thomson discovered the electron through his cathode ray experiments, leading to the plum pudding model of the atom which depicted electrons embedded in a positively charged sphere. Thomson's discovery of the electron in 1897 was crucial because it was the first indication that atoms are made up of smaller components.

Ernest Rutherford, through his famous gold foil experiment, disproved Thomson's model by demonstrating that atoms have a small, dense, positively charged nucleus, leading to the planetary model of the atom. In 1911, Rutherford's experiment showed that a majority of the atom is empty space, with the nucleus occupying a central position.

Theoretical work by Max Planck and Albert Einstein on quantum mechanics and the photoelectric effect laid the groundwork for quantum theory, which further refined atomic models. Planck's work on quanta of energy and Einstein's explanation of the photoelectric effect were significant in the development of quantum mechanics.

Niels Bohr proposed that electrons travel in orbits around the atom's nucleus, with energy levels quantized, leading to his Bohr model of the atom in 1913. Bohr's quantum leap concept explained atomic emission spectra and established the idea of principle energy levels within atoms.

Further advancements were made by J.C. Chadwick who discovered the neutron in 1932, which added another fundamental particle to the atomic model and led to a better understanding of isotopes and atomic mass.

Today's atomic model, known as the quantum mechanical model, incorporates these discoveries but dispenses with the idea of fixed orbits for electrons, instead modeling their locations as probability distributions described by the wave functions in Schrodinger's equation.