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Like the periodic table, the list below organizes the elements by the number of protons in their atoms; it can also be organized by other properties, such as atomic weight, density, and electronegativity. For more detailed information about the origins of element names, see List of chemical element name etymologies.
Species with a single charge are univalent (monovalent). For example, the Cs + cation is a univalent or monovalent cation, whereas the Ca 2+ cation is a divalent cation, and the Fe 3+ cation is a trivalent cation. Unlike Cs and Ca, Fe can also exist in other charge states, notably 2+ and 4+, and is thus known as a multivalent (polyvalent) ion. [15]
Here [Ne] refers to the core electrons which are the same as for the element neon (Ne), the last noble gas before phosphorus in the periodic table. The valence electrons (here 3s 2 3p 3 ) are written explicitly for all atoms.
Periodic table of the chemical elements showing the most or more commonly named sets of elements (in periodic tables), and a traditional dividing line between metals and nonmetals. The f-block actually fits between groups 2 and 3 ; it is usually shown at the foot of the table to save horizontal space.
A mnemonic is a memory aid used to improve long-term memory and make the process of consolidation easier. Many chemistry aspects, rules, names of compounds, sequences of elements, their reactivity, etc., can be easily and efficiently memorized with the help of mnemonics.
Fig. 1. Electron sharing in multivalent atomic binding. The dots and crosses represent the outer electrons of the two different species in each molecule. In ammonia (a), N is connected to three H atoms and is trivalent. In carbon tetrachloride (b), C is connected to four Cl atoms and is tetravalent.
The construction of the periodic table ignores these irregularities and is based on ideal electron configurations. [2] Note the non-linear shell ordering, which comes about due to the different energies of smaller and larger shells.
Charges that are positive are called cations. Charges that are negative are called anions. Elements in the same group have the same charge. A group in the periodic table is a term used to represent the vertical columns. The noble gases of the periodic table do not have a charge because they are nonreactive. Noble gases are considered stable ...