Formulae commas

The site and its occupancy are represented by two right lower indexes separated by a comma. The first index indicates the type of site the second one indicates the number of atoms in this site. (Aa, for instance, means an atom A on a site occupied by A in the ideal structure, whereas AB represents an atom A in a site normally (ideally) occupied by B). A formula such as MM)1 x v or (Mi 1 Jv represents a disordered alloy, whereas... 

A comma separates the formulas Fe and Fe for the ions involved in the reduction half-reaction. The formulas are not separated by a vertical line, because there is no phase boundary between these ions. The Fe and Fe " ions exist in the same aqueous solution. 

Tetrachlorodibenzo-/>-dioxin (commas are left out of all formulae for brevity) Semi-permeable membrane device... 

According to this notation, the main symbol in a formula shows the species (usually elements) present in a certain site. The -> vacancies are normally denoted by the italicized symbol V. Sometimes the vacant sites may also be indicated by other symbols, such as square box ( ), especially when the symbol ofvanadium (V) is present. The right lower indexes may indicate the species occupying this crystallographic site in an ideal lattice, or may show that this position is interstitial (subscript i). The second right lower index, if any, indicates the occupancy and should be separated by a comma. 

Use the formula prefix + root + suffix to put the name together. The full name of this compound is 2-ethyl-1-butene. Remember that a hyphen is placed between numbers and letters, and commas are placed between consecutive numbers. 

Note that generally we write a hyphen between a number and a letter and a comma between a number and another number in the name (by a worldwide agreement amongst chemists, the names of the formulae are in British format), e.g. 2,2-dimethylpropane. 

Berzelius went further in his attempt to simplify the science. He joined the symbols of the elements to represent the simplest parts of compounds. Thus copper oxide was written CuO, and zinc sulfide ZnS. He had, at first, denoted the number of oxygen atoms by dots and the number of sulfur atoms by commas thus carbon dioxide was C and carbon disulfide was C. But he soon discarded these dots and commas, although for decades after, mineralogists utilized this method of writing the formulas of minerals. 

Least Common Multiples When writing chemical formulas or balancing a chemical equation, being able to identify the least common multiple of a set of numbers can often help. Your graphing calculator has a least common multiple function that can compare two numbers. On a TI-83 Plus or similar graphing calculator, press MATH >- 8. The screen should read lcm(. Next, enter one number and then a comma followed by the other number and a closing parenthesis. Press ENTER, and the calculator will show the least common multiple of the pair you entered. 

Three parameters need to be entered. The Set Target Cell is where you enter the cell containing the entered formula. Entering signs for the cell is optional. If you click on the cell to enter (either before or after opening Solver), they are automatically entered. The Equal To is where you enter the value that the equation is set to (0, in this case). And By Changing Cells is where you enter the cell or cells containing the variable or variables (x, in this case). If you have more than one variable cell, insert a comma between each cell entry. Since we don t know the value of the x cell, we may leave it empty, or we may put an estimated initial value in the cell. 

The name of the variable to be solved for must be included at the end of the equation and separated from it by a comma. Mathematica s third kind of equal sign, a double equal sign, must be used in equations to be solved. Another use of this equal sign is in asking Mathematica to test whether an equality if true or false. The resulting output is the standard quadratic formula ... 

It is impossible to derive formulae for n and A of (2) which are entirely analogous to the formulae of the Rayleigh-Schrodinger theory, except that in all scalar products N occurs before the comma, instead of n. This will not be done here as we can restrict ourselves to the first approximation. We find that... 

For more details on crysfol chemical formulae, peuticulaiy for the meaning of the symbols and the commas, semi-colons and small letters within the superscripted square brackets used in the crystal chemical formulae, see the contribution of Uma-de-Faria in this book. 

The goal is to construct a proof tree. Starting from the sequent, and applying step by step some adapted rule, the proof consists on eliminating the connectors. These rules are shown in Figure 1 where is an atom F,G and H are formulas E and A are blocs of formulas separated by commas. The attribute indicates whether the rule is apphed at left (L), at right (R) or to the whole sequent (empty attribute). 

Sequents If E is a multiset of formulas separated by and is a formula then E h is a sequent. By taking E as a multiset we will implicitly assume that the sequent comma is associative and commutative. E is called the antecedent of the sequent and cp the succedent. 

Consider a simple example we are given a pentapeptide known to contain valine (two residues), leucine (one residue), histidine (one residue), and phenylalanine (one residue), as determined by hydrolysis and automatic amino add analysis. With this information we can write the molecular formula of the protein in the following way, using commas to indicate that the sequence is unknown ... 

Only those substances whose compositions were known at least qualitatively have been included. For the notation of the formulae see section 1.2. In the formulae for solid solutions, paraitheses have been used with the host atom or host compound listed first and separated by a comma firom the additive, e.g. (Te, Se)Sn. Phases which cannot be assigned to a specific stoichiometry, for whatever reason, and which cannot be explained as a solid solution, are identified by the symbols of their atoms, separated by a comma, and not enclosed in parentheses, e.g. Sb,Te. 

This requires the use of a logic function of the if-then-else type because, depending on whether the condition is satisfied or not, an appropriate choice of equation must be made. The logic function used by Lotus 1-2-3 is of the following form IF (Condition, x,y), which may be translated as If condition is true (nonzero), then x, or else y. In the present case put the condition T2 > TG + 100, followed by the two expressions separated by commas. Noting that the ASTM temperature and the desired temperature in columns E and B, respectively are in °C, the actual formula which is stored in cell U7 appears as follows ... 

The first number is the list code, the number 13 gives the number of bytes of the list including the byte count, followed by the different fragments, separated by The inverted commas were included to indicate start and end of the formula string, they do not belong to the list, as do the blanks between the numbers and the string. 

Only those compoimds whose compositions were known at least qualitatively have been included. In the formulae for solid solutions parentheses have been used for elements substituting each other the elements enclosed in parentheses are also arranged alphabetically and separated by a comma. For reasons of clearness and depending on the problem, a series of solid solution may be presented in two different ways (e.g. DyTe-ErTe = DyxEri jTe). If the separation of a substance formula is necessary, a multiplication sign is used and the second line is indented. 

The terms left and right refer to the mutual positions of the heteronuclear elements in the chemical formula. If the heteronuclear coordination is formed by one kind of atom only, one of the values for / or r is zero and therefore left out. The position of the comma before or after the remaining number determines uniquely the kind of element forming the coordination polyhedron. If no comma is found the number corresponds to the total heteronuclear coordination. As described above, the number of atoms in the coordination polyhedron can be extended optionally by a small letter which characterizes the geometrical shape of the coordination polyhedron. 

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