Search results
Results From The WOW.Com Content Network
Polyatomic ions often are useful in the context of acid–base chemistry and in the formation of salts. Often, a polyatomic ion can be considered as the conjugate acid or base of a neutral molecule. For example, the conjugate base of sulfuric acid (H 2 SO 4) is the polyatomic hydrogen sulfate anion (HSO − 4).
An atom (or ion) whose oxidation number increases in a redox reaction is said to be oxidized (and is called a reducing agent). It is accomplished by loss of one or more electrons. The atom whose oxidation number decreases gains (receives) one or more electrons and is said to be reduced. This relation can be remembered by the following mnemonics.
The cation is always named first. Ions can be metals, non-metals or polyatomic ions. Therefore, the name of the metal or positive polyatomic ion is followed by the name of the non-metal or negative polyatomic ion. The positive ion retains its element name whereas for a single non-metal anion the ending is changed to -ide.
Each ion can be either monatomic (termed simple ion), such as sodium (Na +) and chloride (Cl −) in sodium chloride, or polyatomic, such as ammonium (NH + 4) and carbonate (CO 2− 3) ions in ammonium carbonate. Salts containing basic ions hydroxide (OH −) or oxide (O 2−) are classified as bases, such as sodium hydroxide and potassium oxide.
Ions consisting of only a single atom are termed atomic or monatomic ions, while two or more atoms form molecular ions or polyatomic ions. In the case of physical ionization in a fluid (gas or liquid), "ion pairs" are created by spontaneous molecule collisions, where each generated pair consists of a free electron and a positive ion. [5]
In chemistry, isomers are molecules or polyatomic ions with identical molecular formula – that is, the same number of atoms of each element – but distinct arrangements of atoms in space. [1] Isomerism refers to the existence or possibility of isomers. Isomers do not necessarily share similar chemical or physical properties.
The phosphotungstate anion, an example of a polyoxometalate. In chemistry, a polyoxometalate (abbreviated POM) is a polyatomic ion, usually an anion, that consists of three or more transition metal oxyanions linked together by shared oxygen atoms to form closed 3-dimensional frameworks.
Charge numbers for ions are denoted in superscript (e.g. Na + indicates a sodium ion with a charge number of positive one). Atomic numbers are charge numbers of atomic nuclei. Charles's law When the pressure on a sample of a dry gas is held constant, the Kelvin temperature is directly proportional to its volume. chelating agent chelation