Size of negatively-charged atom. The size of the atom on which the negative charge rests also effects the stability. As a general rule, negative charges prefer to rest on larger atoms, as the charge can spread over a much larger region of space (making it more stable) than when the charge is localized in a much smaller space on a smaller atom. To better understand unstable atoms, it helps to appreciate what constitutes stability. In the familiar planetary model, an atom consists of a nucleus of heavy positively charged particles, called protons, and electrically neutral ones called neutrons. Orbiting the nucleus is a cloud of lighter, negatively charged electrons. When it contains fewer electrons than protons, the atom is called a cation, or positively charged ion. Conversely, when it contains more electrons than protons, the atom is called an anion, or negatively charged ion. The number of electrons that surround the nucleus determines whether or not an atom is electrically charged or neutral.
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Sometimes atoms gain or lose electrons. The atom then loses or gains a 'negative' charge. These atoms are then called ions. Positive Ion - Occurs when an atom loses an electron (negative charge) it has more protons than electrons.; Negative Ion - Occurs when an atom gains an electron (negative charge) it will have more electrons than protons.; The following image shows Na losing an. Whenever an atom contains excess negative charge, it is called a negative ion.This means that the atom picked up negative charges from another atom. The atom that lost the electrons becomes a.
(click for larger image) The Rutherford Atom for Carbon Ernest Rutherford's original atomic model is now understood to be inaccurate, but it retains its meaning as an icon today. The nucleus consisting of protons and neutrons, here shown in red, is surrounded by orbiting electrons, shown in blue. (click for larger image) The Schrodinger Atom for Carbon Erwin Schrodinger's model is a more correct representation. It includes electron clouds. | An atom is the smallest particle into which an element can be divided without losing its chemical identity. Atoms consist of a heavy central nucleus surrounded by a cloud of negatively charged particles called electrons. The nucleus contains positive particles (protons) and electrically neutral particles (neutrons). The number of protons is called the atomic number. This number uniquely identifies each chemical element. In turn, protons and neutrons are composed of quarks. An element is a chemical substance that is made up of single kind of atom. Iron, carbon, and hydrogen are all elements. A molecule is formed when two or more atoms of any kind of element are joined together chemically. If a molecule contains two or more different elements, it is known as a compound. A water molecule is a compound of the elements hydrogen and oxygen. If an atom or molecule becomes electrically charged by gaining or losing one or more electrons, it becomes an ion. If the atom gains electrons, it has a negative charge. If it loses electrons, it has a positive charge. | (click for larger image) Bohr Model of Calcium Bohr originally developed his atomic model to demonstrate the way in which electrons of hydrogen atoms changed orbits. Physicists today know that this version is not completely accurate, but it is still used because it offers a clear explanation of atomic structure at an introductory level. (click for larger image) Bohr Model of a Calcium Ion The calcium molecule above has gained two negatively charged electrons to become a calcium ion. |
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Negatively Charged Atoms
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