The shortcuts for Windows 7. If you have not made the leap to Windows 8, this little cheat sheet will help you work more efficiently with Windows 7. Note: This list is part of Greg Shultz's comprehensive collection of Windows keyboard shortcuts, available as a PDF download. Also read: Free cheat sheet of 100 Windows 8 keyboard shortcuts.
i just ran across a problem asking me to identify the valence electrons on a sulfur atom in a sulfate ion. my understanding is that sulfate ion = 4 oxygen + 1 sulfur atom and has a 2- charge. now, in the answer to this question, it reads: sulfur in a sulfate ion has 12 valence electrons, its original six... *which i was able to find; 1s2,2s2,2p6,3s2,3p4 plus 6 more from the oxygens to which it is bonded.
Metal. Valency: Since there are 4 electrons in the valence shell, they can make use of these electrons in the bond formation to get octet configuration. Hence their usual valency is 4. However the group 14 elements other than carbon can also show the maximum valency 6 due to the presence of available d-orbitals in them. But carbons maximum valence is 4 due to non availability of d-orbitals. Oxidation number: Their usual stable oxidation number is +4.