The degree of combining power of an atom (or radical) as shown by the number of atoms of hydrogen (or of other monads, as chlorine, sodium, etc.) with which it will combine, or for which it can be substituted, or with which it can be compared; thus, an atom of hydrogen is a monad, and has a valence of one; the atoms of oxygen, nitrogen, and carbon are respectively dyads, triads, and tetrads, and have a valence respectively of two, three, and four.
measure of the number of antigens contained in a vaccine.
A small positive or negative whole number, also called oxidation number, which indicates the net number of electrons gained or lost in the formation of an ion, or the number of electrons the substance can donate or accept in a chemical reaction, and thus the numbers of each kind of ion necessary for a balanced chemical reaction. For example, two hydrogen ions (each with a valence of +1) must be present for each ion of oxygen (-2) to form a molecule of water (H2O).
a signed integer describing the combining power of an atom.
the tendency of elements to form compounds through a shift of electronic structure.
In covalent compounds, the valence of an atom is the number of bonds it forms to other atoms.
The number of electrons which an atom can give or take up when reacting with other atoms to form a chemical compound.
(va-lence) (equivalent to oxidation state) An integer (whole number) that represents the power of one element to combine with another. For example, if hydrogen (H) and chlorine (Cl) both have a valence of 1, oxygen (O) -2 and nitrogen (N) +3, the valence-balancing principle gives the formulas HCl (hydrogen chloride or hydrochloric acid), H2O (water), NH3 (ammonia), and HNO3 (nitric acid). The subscript numbers indicate the relative numbers of atoms of each element. Many elements have multiple valences; for example, the element vanadium (V) occurs in four valences, +2, +3, +4, and +5, and iron (Fe) occurs in two valences, +2 and +3.
Number of electrons gained, lost, or shared by an atom in bonding to one or more other atoms.
(biology) a relative capacity to unite or react or interact as with antigens or a biological substrate
(chemistry) a property of atoms or radicals; their combining power given in terms of the number of hydrogen atoms (or the equivalent)
a likely charge on an element ion
1a) The capacity of an atom or group of atoms to combine in specific proportions with other atoms or groups of atoms; b) an integer, often one of several for any given element, used to represent this capacity in terms of an arbitrary assignment of 1 to an atom or group capable of forming a single bond with chlorine and of –1 to an atom or group capable of forming a single bond with hydrogen; 2) The capacity of something o unite, react, or interact with something else; 3) the number of components of an antigen molecule to which an antibody molecule can bind.
Within the scope of combination vaccines the valence of the vaccine is the number of different vaccines which are included in the preparation e.g. DTP vaccine is said to be trivalent.
The number of bonds that an atom can form.
The electrons occupying the highest principle energy level in an atom.
One level of an orbital Valence electrons The outermost electrons in an atom
The outermost electron shell or subshell of an atom.
(n.) The number of edges connected to a vertex in a graph; for example, every node in a regular square mesh has a valence of 4. Confusingly, valence also means the number of branches below a tree node, which is one fewer than the number of edges incident to that node - every node in a binary tree has a valence of 2. The term arity is sometimes also used in this sense.
A positive number that characterizes the combining power of an element for other elements, as measured by the number of bonds to other atoms that one atom of the given element forms upon chemical combination: hydrogen is assigned valence 1, and the valence is the number of hydrogen atoms, or their equivalent, with which an atom of the given element combines.
A property of ions or of radicals determining the number of ions with which they can combine in chemical reactions.
A whole number (positive or negative) representing the power of one element to combine with another. In general terms, the valence number represents the number of electrons in an atom or combined group of atoms which can be easily given up or accepted to react with or bond to another atom or group of atoms to form a molecule.
The number of single bonds an atom can form, also measured as the number of hydrogen atoms that typically bond to an atom of an element. For example, in H2O, oxygen has a valence of two; in CH4, carbon has a valence of four.
"Number of type of successors to a relationship. Also called the n-arity. Most relationships have a valence of 2 (binary relationships), but relationships with a valence of 3 or 4 are not uncommon."
Related to the outer shell or orbit of an atom.
In chemistry, valence, also known as valency or valency number, is a measure of the number of chemical bonds formed by the atoms of a given element. Over the last century, the concept of valence evolved into valence bond theory (1927) and then into modern valence bond theory (1990s).