Atomic Theory

Free Articles

“Follow the Carbon.” Follow the What?
February 2008 (pp16–19)

Author: Lora Bleacher
Chemistry Connections:
 Atomic Theory, Nuclear, Organic/Biochemistry
Description:
 Describes the Sample Analysis at Mars (SAM) suite of instruments on board the Mars Science Laboratory (MSL), to land on Mars in late 2009 and stay there roving the surface collecting data. Instruments include laser spectrometer, gas chromatograph, and quadrupole mass spectrometer. Discussion of the value of studying carbon as an essential ingredient of life and its role in organic compounds ensues. Talks about isotopes of carbon providing information about the origin of the organic materials the SAM might detect.

ChemMystery: Real or Fake? The James Ossuary Case
February 2006 (pp 8–10)

Author: Lois Fruen
Chemistry Connections:
 Atomic Theory, Equilibrium, History/Biography, Nuclear, Organic/Biochemistry
Description:
 Discusses methods used to authenticate antiquities, focusing on radiocarbon dating. The process and the background science are described. Other methods described: hardness and density testing, microscopic analysis of mineral composition, mass spectrometry to measure O-18 to O-16 isotope ratios. Scientists reported the artifacts were fake, but then further research by other scientists refuted the fakery claims. The question remains unanswered. Chemistry centers on isotopic composition and presence of carbon dioxide in groundwater dissolving calcite (equilibrium equations provided).

Super Fibers
February 2006 (pp 11–13)

Author: Christen Brownlee
Chemistry Connections:
 Atomic Theory, Bonding
Description:
 Talks about infantry wear in the future, providing everything from personal air conditioning to health readings to two-way communication, to changing camouflage matching the terrain, to projectile protection, all designed within the fabric of the uniform, based on carbon nanotubes. Discusses the discovery and history of development and production of nanotubes, and projected roles for fibers made from them, including the infamous space elevator and worldwide electricity distributor.

Articles available on the ChemMatters DVD

Where Do Chemical Elements Come From?
October 2009 (pp 6–8)

Author: Carolyn Ruth 
Chemistry Connections:
 Atomic theory, Nuclear, Periodicity, Reactions
Description:
 Describes the various processes for producing the various elements in stars of various types. Fusion, fission and “r” reactions detailed. Spectroscopy used to identify the elements in stars and gaseous clouds.

ChemHistory: The New Alchemy
October 2006 (pp 15–17)

Author: Michael McClure
Chemistry Connections:
 Atomic theory, History/Biography, Nuclear, Periodicity
Description:
 Relates the history of discovering/explaining various nuclear reactions (fusion, radioactivity, fission, transmutation). Working with transuranium elements, Seaborg proposed actinide series.

ChemSumer: The Chemistry of Digital Photography and Printing
February 2006 (pp 4–7)

Author: Brian Rohrig
Chemistry Connections:
 Atomic Theory, Bonding, Metals/Nonmetals, Periodicity
Description:
 Begins with a very brief description of film photography and its chemistry. Then describes the role of “n” and “p” type semiconductors to form diodes, photosites or pixels, in the digital camera sensor. Also discusses differences between black and white and color sensors. Then it discusses inkjet vs. laser printing processes, focusing on charge differences to transfer the image or text.

Einstein’s Miraculous Year
December 2005 (pp 4–6)

Author: Doris Kimbrough
Chemistry Connections:
 Atomic Theory, History/Biography, Solids/Liquids/Gases
Description:
 Discusses three main problems tackled by Einstein in 1905: photoelectric effect, the nature of atomic structure, and the space-time continuum. Photoelectric effect: describes light as electromagnetic waves, and states that frequency, not intensity determines if electrons are ejected when light shines on a metal, and higher frequency means faster electrons ejected. Einstein’s answer: think of light as a particle (photon) here, not a wave. Atomic theory: Einstein explained Brownian motion as the motion of atoms and molecules bumping into each other, and calculated the size of atoms based on his observations, cementing the idea of atoms for doubting scientists. Special theory of relativity: Einstein showed that time and space are relative, depending on the frame of reference of the observer. Diagram illustrates photoelectric effect.

Antimatter
April 2005 (pp 10–13)

Author: Brian Rohrig
Chemistry Connections:
 Atomic Theory, Nuclear
Description: 
Defines antimatter and establishes the existence of antimatter particles for every known particle in the universe. Discusses history of discoveries of antimatter particles, their existence in the universe, the huge instruments needed to create these particles (Stanford Linear Accelerator and CERN), and the energies involved when these particles and antiparticles collide. Talks about how antimatter is created for use in positron emission spectroscopy (PET) scans of the body.

MysteryMatters: Scanning Electron Microscopy Solves a Mystery!
December 2003 (pp 17–19)

Author: Tim Graham
Chemistry Connections:
 Atomic Theory, Reactions
Description:
 Use of scattering electron microscopy (SEM) to analyze chemical composition of defective car paint job. Diagrammatic scheme shows basics of SEM operation, results of paint analysis, and answers to the cause of defective paint.