The valence electrons, the outermost shell of electrons, are the largest determinant of how an atom reacts chemically to other substances in its environment. The number and arrangement of the outermost electron shell are important, as is the placement of the shell itself, since different shells hold different numbers of electrons.Know More
Chemical processes are involved in nearly all natural phenomena, including all the activities of life. The number of valence electrons is the biggest determinant of how any particular particle behaves chemically. Most valence shells hold up to eight electrons, while the outermost shells of hydrogen and helium only have room for two. The difference between the number of electrons in a neutral atom and the number of electrons needed to fill the outermost valence shell determines the reactivity of a given element.
When an atom or ion has only full electron shells, it is less chemically reactive; that is, it is less prone to form covalent bonds. The noble gases, such as helium and neon, are almost totally nonreactive because of their naturally full valence shells. Conversely, atoms only one or two electrons away from full valence shells, whether in the positive or negative direction, are the most reactive elements.Learn more in Molecular Biology & DNA
Sulfur has six valence electrons, meaning that each atom of this element has six electrons in its outermost shell. The number of valence electrons that each element has can be predicted based on its location on the periodic table, though this only applies to neutral atoms. An element's main group number indicates how many valence electrons each atom of that element will have, and because sulfur is part of group six on the periodic table, this indicates that this element has six electrons in its outermost electron "shell."Full Answer >
The first ionization energy generally decreases down a group due to the increasing distance of the valence electrons from the nucleus of an atom. The increasing gap lowers the attractive force of the protons that pull the electrons closer to the nucleus.Full Answer >
The Lewis dot structure for HF, hydrofluoric acid, is drawn by representing the bonds between each atom and showing all of the valence electrons in the structure. The Lewis dot structure takes a few moments to draw and requires basic knowledge of chemistry.Full Answer >
The nucleus of an atom always has a positive net charge of one or greater. The presence of protons contained exclusively in the nucleus causes a positive charge.Full Answer >