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  2. Donor number - Wikipedia

    en.wikipedia.org/wiki/Donor_number

    In chemistry a donor number (DN) is a quantitative measure of Lewis basicity.A donor number is defined as the negative enthalpy value for the 1:1 adduct formation between a Lewis base and the standard Lewis acid SbCl 5 (antimony pentachloride), in dilute solution in the noncoordinating solvent 1,2-dichloroethane with a zero DN.

  3. Degree of unsaturation - Wikipedia

    en.wikipedia.org/wiki/Degree_of_unsaturation

    For hydrocarbons, the DBE (or IHD) tells us the number of rings and/or extra bonds in a non-saturated structure, which equals the number of hydrogen pairs that are required to make the structure saturated, simply because joining two elements to form a ring or adding one extra bond (e.g., a single bond changed to a double bond) in a structure reduces the need for two H's.

  4. Propagation of uncertainty - Wikipedia

    en.wikipedia.org/wiki/Propagation_of_uncertainty

    For example, the 68% confidence limits for a one-dimensional variable belonging to a normal distribution are approximately ± one standard deviation σ from the central value x, which means that the region x ± σ will cover the true value in roughly 68% of cases. If the uncertainties are correlated then covariance must be taken into account ...

  5. Benson group increment theory - Wikipedia

    en.wikipedia.org/wiki/Benson_group_increment_theory

    Once this is determined, all one needs to do is take the total value of Δ f H, subtract the Δ f H caused by the C−(C) 2 (H) 2 group(s), and then divide that number by two (due to two C−(C)(H) 3 groups), obtaining the value of the C−(C)(H) 3 group. From the knowledge of these two groups, Benson moved forward obtain and list functional ...

  6. List of dimensionless quantities - Wikipedia

    en.wikipedia.org/wiki/List_of_dimensionless...

    Bodenstein number: Bo or Bd = / = Max Bodenstein: chemistry (residence-time distribution; similar to the axial mass transfer Peclet number) [2] Damköhler numbers: Da = Gerhard Damköhler: chemistry (reaction time scales vs. residence time)

  7. Ion transport number - Wikipedia

    en.wikipedia.org/wiki/Ion_transport_number

    The practical importance of high (i.e. close to 1) transference numbers of the charge-shuttling ion (i.e. Li+ in lithium-ion batteries) is related to the fact, that in single-ion devices (such as lithium-ion batteries) electrolytes with the transfer number of the ion near 1, concentration gradients do not develop. A constant electrolyte ...

  8. Wiener index - Wikipedia

    en.wikipedia.org/wiki/Wiener_index

    The total time for this approach is O(nm), where n is the number of vertices in the graph and m is its number of edges. For weighted graphs, one may instead use the Floyd–Warshall algorithm [ 13 ] [ 14 ] [ 15 ] or Johnson's algorithm , [ 16 ] with running time O( n 3 ) or O( nm + n 2 log n ) respectively.

  9. Chemical table file - Wikipedia

    en.wikipedia.org/wiki/Chemical_table_file

    An MDL Molfile is a file format for holding information about the atoms, bonds, connectivity and coordinates of a molecule.. The molfile consists of some header information, the Connection Table (CT) containing atom info, then bond connections and types, followed by sections for more complex information.