Recently you have been reading about valence electrons, briefly describe what valence electrons are and explain why the number of valence electrons for a main-group element is equal to its Roman numeral group number.
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Valence electrons are the electrons located in the outermost energy level or shell of an atom. Show more…
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Valence electrons are the most important electrons in determining the chemical properties of main group elements. (Main group elements are also known as representative elements.) You determine how many valence electrons a representative element has by looking at the Group number of the column. Note: There are two designations for columns - Roman Numerals were the original way that columns were designated when the current periodic table was developed nearly a hundred years ago. Roman numerals with the letter "A" are more descriptive: For representative elements, they indicate the number of valence electrons; and the "A" means main group (representative) elements. For transition metals, the "B" indicates transition metals and the Roman numeral represents the number of outer electrons in the metals that are most important. The sequential numbers of columns is a more modern designation: If you drop the first digit for Groups 13 - 18, then the number of valence electrons is given. You can also determine the number of valence electrons by summing the highest level and p electrons in an atom. Representative elements in the same column in the have similar chemical properties because they have the same number of valence electrons. The textbook calls the last electron added to the electron configuration for an element a "Distinguishing Electron." Distinguishing electrons are related to valence electrons, but the terminology is used more to indicate the classification of the element; e.g., if the element is a transition metal, main group element, etc. For the following elements, type the Group number, number of valence electrons, and element symbol: 1s²2s²2p⁶3s²3p⁶ Group number Number of valence electrons
Madhur L.
valence electrons basic atoms electron shells atoms molecules electron distribution harm living organisms interact with other molecules charge distribution electrons The of each element have a characteristic number of arranged in . The number of determines what types of bonds or ions the atoms may form, so the chemical reactivity of an atom arises from its . The properties of compounds emerge from the arrangement of their constituent atoms and of the bonds between them. Thus, a wide variety of with very different chemical properties can be made from the same . Each molecule has a distinctive size, shape, and , which determine its highly specific ability to . Compounds in chemical wastes may contaminate the environment if their atoms are combined in new arrangements that .
Josee P.
1. Valence electrons are the electrons in the outermost energy level of the atom. This concept applies to only certain atoms on the periodic table. Which atoms? Don't name them all! Tell me the general name... 2. How many valence electrons are in each of the following atoms? A. K B. Ge C. Te D. In E. F F. Br G. Xe H. P I. O J. Si K. Sr L. Mg M. B N. N O. Al P. Rb 3. Explain why all alkali metals make +1 cations. Be sure to talk about electron configurations! You might even want to give the electron configuration of the first three alkali metals...
Adi S.
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