Here are four different ways chemists use to show a molecule of ammonia. In the colored molecule models, nitrogen atoms are blue and hydrogen atoms are white.
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Windows to the Universe original artwork by Randy Russell.


Most things around us are made of groups of atoms connected together into packages called molecules.

Molecules are made from atoms of one or more elements. Some molecules are made of only one type of atom. Other molecules are very large and are made of hundreds of atoms.

Even large molecules are so small that you would not be able to see only one molecule of something. But when thousands of molecules are together, they might look like a glass of water, a tree or even your computer screen!

Last modified September 17, 2010 by Randy Russell.

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Windows to the Universe, a project of the National Earth Science Teachers Association, is sponsored in part is sponsored in part through grants from federal agencies (NASA and NOAA), and partnerships with affiliated organizations, including the American Geophysical Union, the Howard Hughes Medical Institute, the Earth System Information Partnership, the American Meteorological Society, the National Center for Science Education, and TERC. The American Geophysical Union and the American Geosciences Institute are Windows to the Universe Founding Partners. NESTA welcomes new Institutional Affiliates in support of our ongoing programs, as well as collaborations on new projects. Contact NESTA for more information. NASA ESIP NCSE HHMI AGU AGI AMS NOAA