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CAS, Chemical Abstracts Service Home Page

CAS, Chemical Abstracts Service Home Page
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Periodic Table of the Elements by WebElements Where to find MSDS and SDS on the Internet General Sites These sites have large collections of MSDS and are a good place to start your search. [Top] [General Sites] [Governmental] [Chemical Companies] [Pesticides] [Misc] Government and Non-Profit Sites The first two sites return all sorts of chemical information; the remainder are written more for humans rather than corporate lawyers and are good sites for non-chemists to find information. Chemical Manufacturers and Suppliers The best place to start if you have a bottle from that particular manufacturer! Pesticides (herbicides, insecticides, fungicides, nematicides, rodenticides etc.) A great place to start for farmers, home gardeners or someone who got too close to a crop dusting plane. Miscellaneous Look here for manufacturers whose primary business is not chemicals.

Mineralogy Database - Mineral Collecting, Localities, Mineral Photos and Data Category:Chemistry The main article for this category is Chemistry. Subcategories This category has the following 70 subcategories, out of 70 total. Pages in category "Chemistry" The following 98 pages are in this category, out of 98 total. Covalent radius The covalent radius, rcov, is a measure of the size of an atom that forms part of one covalent bond. It is measured either in picometres (pm) or ångströms (Å), with 1 Å = 100 pm. In principle, the sum of the two covalent radii should equal the covalent bond length between two atoms, R(AB) = r(A) + r(B). Moreover, different radii can be introduced for single, double and triple bonds (r1, r2 and r3 below), in a purely operational sense. These relationships are certainly not exact because the size of an atom is not constant but depends on its chemical environment. The bond lengths R(AB) are measured by X-ray diffraction (more rarely, neutron diffraction on molecular crystals). Table of covalent radii the covalent radius is measured approximately as the radius of an atom's core which is in contact with the core of an adjacent atom in a bonded situation A different approach is to make a self-consistent fit for all elements in a smaller set of molecules. References Log in / create account

WebElements Periodic Table of the Elements My window is too large and wider than my screen. How to I resize it back? Something was downloaded to my computer while I was away this week. (My husband probably thought it was ok.) Now when I open an email thru Outlook it’s huge – it goes way off the screen to the right. I don’t know how to resize this or fix this. Can you please tell me in simple one and two syllable words just what to do? Oh, those husbands. The too-wide window could be the result of a download, but it’s also possible that it’s not his fault. Normally, of course, you can resize a window by using the mouse and clicking on and dragging the border of the window. When you’re in one of those too-wide windows, do the following. I believe it’s still the case that while a mouse is technically listed as a requirement for Windows, there is a keyboard interface for everything.

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