Big Chemical Encyclopedia

Chemical substances, components, reactions, process design ...

Articles Figures Tables About

Coefficient in formulas

For molecules containing light atoms, we accordingly neglect this effect of finite nuclear volume or field shift, but other effects prevent exact application of isotopic ratios that one might expect on the basis of a proportionality with in formula 13 instead of total F. For this reason we supplement term coefficients in formula 8 for a particular isotopic species i with auxiliary coefficients [54],... [Pg.264]

Exact numbers, such as the stoichiometric coefficients in a chemical formula or reaction, and unit conversion factors, have an infinite number of significant figures. A mole of CaCb, for example, contains exactly two moles of chloride and one mole of calcium. In the equality... [Pg.14]

Compound and Chemical Formula Specific Gravity or Density Solubility in 100 Parts Diffusion Coefficient in Air (cm /sec) Melting Point, C Boiling Point, C... [Pg.150]

The slope of the curve in the transitional zone changes from 135 to 180°. It shows that the exponent in changes as follows 0 a 1. This means that the friction and inertia forces are commensurable in the process of sedimentation. Several empirical formulas have been proposed for estimating the resistance coefficient in the transition zone. One such correlation is... [Pg.299]

The expansion coefficients determine the first-order correction to the perturbed wave function (eq. (4.35)), and they can be calculated for the known unperturbed wave functions and energies. The coefficient in front of 4>o for 4 i cannot be determined from the above formula, but the assumption of intermediate normalization (eq. (4.30)) makes Co = 0. [Pg.125]

Previously Wright had studied asymptotic relations between the coefficients in two generating functions related by the formula equation... [Pg.133]

Equations are balanced by adjusting coefficients in front of formulas, never by changing subscripts within formulas. On paper, the equation discussed above could have been balanced by writing N6 on the right, but that would have been absurd. Elemental nitrogen exists as diatomic molecules, N2 there is no such thing as an N6 molecule. [Pg.61]

The effect of orientation on the physic-mechanical properties is taken into account with the help of appropriate coefficients in the respective formulas [152,155, 157], The procedures for determining these coefficients are described in the same references. [Pg.22]

About 95% of Escherichia coli is C, H, O and N. The chemical formula for cell composition and the stoichiometric coefficients in (9.2.1) depend on media composition and the environment surrounding die cell.2,4 All die major elements in die above equation have to be balanced. Then die stoichiometric coefficients are identified by solving simultaneously the system of equations ... [Pg.229]

Campbell s Theorem, 174 Cartwright, M. L., 388 Caywood, T. E., 313 C-coefficients, 404 formulas for, 406 recursion relations, 406 relation to spherical harmonics, 408 tabulations of, 408 Wigner s formula, 408 Central field Dirac equation in, 629 Central force law... [Pg.770]

The diffusion coefficient is presumed to decrease due to the cross-linking, as described in formula 9. [Pg.233]

We have written the difference equation (14) at a fixed node x = x. With an arbitrarily chosen node it is plain to derive equation (14) at all inner nodes of the grid. Since at all the nodes x, i = 1, 2,.. ., IV — 1, the coefficients a, and are specified by the same formulae (15), scheme (14)-(15) is treated as a homogeneous conservative scheme. Because of this, we may omit the subscript i in formulae (14)-(15) and write down an alternative form of scheme (14) ... [Pg.153]

Chemical equations are used to describe reactions between compounds. The formulae of the reactants are written on the left-hand side of the equation and the formulae of the products on the right. If a number of molecules of one kind take part in the reaction the number is written as a coefficient in front of the formulae. The two sides of the equation must balance. [Pg.23]

As this relation is correct for all values of s, the coefficients in brackets must vanish The result yields the important recursion formula for the Hermite polynomials,... [Pg.268]

A chemical equation describes a chemical reaction in many ways as an empirical formula describes a chemical compound. The equation describes not only which substances react, but the relative number of moles of each undergoing reaction and the relative number of moles of each product formed. Note especially that it is the mole ratios in which the substances react, not how much is present, that the equation describes. In order to show the quantitative relationships, the equation must be balanced. That is, it must have the same number of atoms of each element used up and produced (except for special equations that describe nuclear reactions). The law of conservation of mass is thus obeyed, and also the "law of conservation of atoms. Coefficients are used before the formulas for elements and compounds to tell how many formula units of that substance are involved in the reaction. A coefficient does not imply any chemical bonding between units of the substance it is placed before. The number of atoms involved in each formula unit is multiplied by the coefficient to get the total number of atoms of each element involved. Later, when equations with individual ions are written (Chap. 9), the net charge on each side of the equation, as well as the numbers of atoms of each element, must be the same to have a balanced equation. The absence of a coefficient in a balanced equation implies a coefficient of 1. [Pg.114]

The equation states that elementary sodium reacts with elementary chlorine to produce sodium chloride, table salt. (The fact that chlorine is one of the seven elements that occur in diatomic molecules when not combined with other elements is indicated.) The numbers before the Na and NaCI are coefficients, stating how many formula units of these substances are involved. If there is no coefficient in a balanced equation, a coefficient of 1 is implied, and so the absence of a coefficient before the Cl2 implies one Cl2 molecule. The equation thus states that when the two reagents react, they do so in a ratio of two atoms of sodium to one molecule of chlorine, to form two formula units of sodium chloride. In addition, it states that when the two reagents react, they do so in a ratio of 2 mol of sodium to 1 mol of chlorine molecules, to form 2 mol of sodium chloride. The ratios of moles of each reactant and product to every other reactant or product are implied ... [Pg.115]

If we know the friction coefficients a, we thus have an explicit formula for the conductivity coefficient. In particular, it is often assumed that a is determined by the well-known Stokes formula ... [Pg.209]

The Law of Conservation of Mass states that the total mass remains unchanged. This means that the total mass of the atoms of each element represented in the reactants must appear as products. In order to indicate this, we must balance the reaction. When balancing chemical equations, it is important to realize that you cannot change the formulas of the reactants and products the only things you may change are the coefficients in front of the reactants and products. The coefficients indicate how many of each chemical species react or form. A balanced equation has the same number of each type of atom present on both sides of the equation and the coefficients are present in the lowest whole number ratio. For example, iron metal reacts with oxygen gas to form rust, iron(III) oxide. We may represent this reaction by the following balanced equation ... [Pg.32]

In this chapter, you learned how to balance simple chemical equations by inspection. Then you examined the mass/mole/particle relationships. A mole has 6.022 x 1023 particles (Avogadro s number) and the mass of a substance expressed in grams. We can interpret the coefficients in the balanced chemical equation as a mole relationship as well as a particle one. Using these relationships, we can determine how much reactant is needed and how much product can be formed—the stoichiometry of the reaction. The limiting reactant is the one that is consumed completely it determines the amount of product formed. The percent yield gives an indication of the efficiency of the reaction. Mass data allows us to determine the percentage of each element in a compound and the empirical and molecular formulas. [Pg.44]

The Addition Formula for the Bessel Coefficients. In certain physical problems we have to reduce a Bessel coefficient of type, /n(i -(- ij) to a form more amenable to compulation. Wc shall now derive tin addition formula which is of great use in these circumstances. From the definition (25.0) we have the expansion... [Pg.101]


See other pages where Coefficient in formulas is mentioned: [Pg.173]    [Pg.283]    [Pg.300]    [Pg.478]    [Pg.170]    [Pg.163]    [Pg.134]    [Pg.177]    [Pg.177]    [Pg.134]    [Pg.48]    [Pg.173]    [Pg.283]    [Pg.300]    [Pg.478]    [Pg.170]    [Pg.163]    [Pg.134]    [Pg.177]    [Pg.177]    [Pg.134]    [Pg.48]    [Pg.218]    [Pg.692]    [Pg.162]    [Pg.1837]    [Pg.1318]    [Pg.153]    [Pg.114]    [Pg.12]    [Pg.389]    [Pg.398]    [Pg.465]    [Pg.213]    [Pg.329]   
See also in sourсe #XX -- [ Pg.131 , Pg.131 ]




SEARCH



Formula In

© 2024 chempedia.info