Microsoft Windows Vista Community Forums - Vistaheads
Recommended Download

Welcome to the Microsoft Windows Vista Community Forums - Vistaheads, YOUR Largest Resource for Windows Vista related information.

You are currently viewing our boards as a guest which gives you limited access to view most discussions and access our other features. By joining our free community you will have access to post topics, communicate privately with other members (PM), respond to polls, upload content and access many other special features. Registration is fast, simple and absolutely free so , join our community today!

If you have any problems with the registration process or your account login, please contact us.

Driver Scanner

Sept. 3, 1803: Dalton Introduces Atomic Symbols

General Technology News

Speedup My PC
  #1 (permalink)  
Old 09-03-2008
Steve's Avatar

Join Date: Sep 2006
Location: Emerald Isle
Posts: 90,159
Steve has a brilliant futureSteve has a brilliant futureSteve has a brilliant futureSteve has a brilliant futureSteve has a brilliant futureSteve has a brilliant futureSteve has a brilliant futureSteve has a brilliant futureSteve has a brilliant futureSteve has a brilliant futureSteve has a brilliant future
Thanks: 24
Thanked 181 Times in 45 Posts
Sept. 3, 1803: Dalton Introduces Atomic Symbols
1803: English chemist-physicist John Dalton starts using symbols to represent the atoms of different elements.
Dalton, considered the father of modern atomic theory, made a logbook entry that day titled, "Observations on the Ultimate Particles of Bodies and their Combinations." It was the first use of symbols to represent the elements of modern chemistry.
He soon had a table of 21 elements arranged by atomic mass, which he presented in a scientific paper the following month. Eventually, he had 36 different symbols.
In his 1805 work, "A New System of Chemical Philosophy," Dalton propounded the tenets of his atomic theory:
  1. The chemical elements are made of atoms.
  2. The atoms of an element are identical in mass.
  3. Atoms of different elements have different masses.
  4. Atoms combine only in small, whole-number ratios like 1:1, 1:2, 2:3, etc.
  5. Atoms can not be created or destroyed.

Dalton's symbols were not the ones we use today, but circles containing distinct symbols (a dot for hydrogen, a cross for sulfur), or circles containing letters (C for copper, L for lead). He used them singly to represent elements and in combination to show compounds.
A decade after Dalton formulated his symbols, Swedish chemist J÷ns Jakob Berzelius simplified the system. Half of Dalton's symbols used letters inside a circle to represent the element. Berzelius organized 47 elements with letters alone, and he based those letters not primarily on the English names, but on the Latin ones. In an era when all Europe's learned men (and the few women who were allowed into schools and universities) knew Latin, the shared language was an international lingua franca.
All but a handful of Berzelius' symbols are still used today. So it's Au for gold and Ag for silver, not the circled G and S of Dalton's original notation.
The simplified notation led the way for English analytical chemist John Newlands to formulate his Law of Octaves and a prototype periodic table of the elements in 1864, but it was Russian chemist Dmitri Mendeleev who really laid it all on the table with 63 elements in 1869. When he flipped his chart to a horizontal table two years later, he created a form much like what you see in chemistry textbooks and on the walls of chem labs today.
Alas, Mendeleev's table was based on atomic mass rather than atomic number, so details like the placement of tellurium and iodine didn't work out. He thought it was a question of inaccurate measurement or other experimental error. It was 1913 before English physicist Henry Moseley reorganized the periodic table by atomic number.
As for Dalton, his name lives on as alternate designation for the atomic mass unit or amu. Microbiologists and biochemists need a convenient measure for large organic molecules. Kilo-u or kilo-amu would be awkward, so a protein molecule might be said to have a mass of 35 kilodaltons, or kDA.
But it's Berzelius' symbols and what they mean that plague first-year chem students: You've got to "get it" before you can do anything else.

Source: History of the Atom, Elementymology

Reply With Quote
Sponsored Links

Thread Tools
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

vB code is On
Smilies are On
[IMG] code is On
HTML code is On
Trackbacks are On
Pingbacks are On
Refbacks are Off

Similar Threads
Thread Thread Starter Forum Replies Last Post
OWASP USA to Be Held in Sept. in NYC Paul Security News 0 08-23-2008 02:30
Will Wright's Spore To Release Sept. 7th Steve General Technology News 0 02-12-2008 21:10
Automatic Updates not installing since Sept/07 CLM microsoft.public.windowsupdate 6 11-30-2007 01:09
Virus, Phishing Rise in Sept. Paul Security News 0 09-27-2007 15:00
Server 2008 Sept. CTP is out SAM-R 8 09-07-2007 22:25

All times are GMT +1. The time now is 09:23.

Driver Scanner - Free Scan Now is part of the Heads Network. See also , and

Design by Vjacheslav Trushkin for
Powered by vBulletin® Version 3.6.7
Copyright ©2000 - 2016, Jelsoft Enterprises Ltd.
Search Engine Optimization by vBSEO 3.6.0 RC 2

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120