The number of dots in the lewis symbol represents the number of valence electrons. The common valency of the element is either equal to the number of dots or 8 minus the number of dots. Ex : For carbon the valency is 4. But valency of nitrogen is 8-5=3
For desialylation, ~1 µg/ml of EPO with or without the L29 sequence were dissolved in 0.1 M MES buffer, pH 6.5, containing 150 mM NaCl, and then incubated with 250 µunits/mL of sialidase from Arthrobacter ureafaciens (Nacalai tesque) at 37 °C for 1 h. Desialyla...
•Chemicalshorthandforacompound•Subscript#tellshowmanyatomsofthatelement•TellswhatelementsitcontainsandratioofatomsNaCl=1atomsodium,1atomchlorineH2O=2atomshydrogen,1atomoxygenFe2O3=2atomsiron,3atomsoxygenCa(OH)2=1calcium,2oxygen,2hydrogen 9 IndependentPracticeCountingAtoms 10 WritingChemicalFormulas Mg...
2. DrawtheelectronsasdotsoneataMmearoundtheatoms symbolinaclockwisefashionstarMngonthetop. 3. A eroneelectronisoneachside,doublethemupunMlyou runoutofelectrons. 4. IE---ErasetheinsidelayersofaBohrmodelanddrawonly theoutermostshell–usedotstorepresenttheelectrons! EXA PLES 1. NaCl Formula: ...