Related Experiment Video
Updated: Jun 28, 2026
12:11
Computation of Atmospheric Concentrations of Molecular Clusters from ab initio Thermochemistry
Published on: April 8, 2020
An algorithm for reducing storage requirements in computer calculation of chemical equilibria.
1Department of Applied Earth Sciences, Stanford University, Stanford, CA 94305, U.S.A.
Talanta
|January 1, 1983
Summary
A new algorithm efficiently stores stoichiometric coefficients for multi-component systems, saving significant computer memory. This method is ideal for microcomputers and complex geochemical calculations.
Area of Science:
- Computational chemistry
- Chemical thermodynamics
- Geochemistry
Background:
- Storing stoichiometric coefficients for complex chemical systems can be memory-intensive.
- Traditional methods using 2D arrays are inefficient for large datasets.
Purpose of the Study:
- To describe an algorithm for efficient storage of stoichiometric coefficients.
- To present FORTRAN code for implementing the algorithm.
- To highlight storage savings for computational chemistry and geochemistry.
Main Methods:
- Developed a novel algorithm for storing stoichiometric coefficients.
- Implemented the algorithm using FORTRAN code.
- Compared storage requirements with conventional 2D array methods.
Main Results:
- The proposed algorithm significantly reduces storage needs compared to 2D arrays.
- Storage savings are particularly beneficial for microcomputers.
- The method is well-suited for large-scale geochemical calculations.
Conclusions:
- The new algorithm offers a more memory-efficient approach to storing chemical system data.
- This advancement supports complex computations on resource-limited systems.
- The FORTRAN implementation provides a practical tool for researchers.
Related Concept Videos
01:21Chemical Equilibria: Systematic Approach to Equilibrium Calculations
Equilibrium calculations for systems involving multiple equilibria are often complex. For example, to calculate the solubility of a sparingly soluble salt in an aqueous solution in the presence of a common ion, one must consider all the equilibria in this solution. Calculations for these systems can be complicated and tedious, so a systematic approach with a series of steps is often helpful. The process is detailed below.
The first step is to identify all the chemical reactions involved, The...
The first step is to identify all the chemical reactions involved, The...
02:05Calculating Equilibrium Concentrations
Being able to calculate equilibrium concentrations is essential to many areas of science and technology—for example, in the formulation and dosing of pharmaceutical products. After a drug is ingested or injected, it is typically involved in several chemical equilibria that affect its ultimate concentration in the body system of interest. Knowledge of the quantitative aspects of these equilibria is required to compute a dosage amount that will solicit the desired therapeutic effect.
A more...
A more...
03:10Chemical Equations
Chemical equations represent the identities and relative quantities of substances involved in a chemical reaction. The substances undergoing reaction are called reactants, and their formulas are placed on the left side of the equation. The substances generated by the reaction are called products, and their formulas are placed on the right side of the equation. Plus signs (+) separate individual reactant and product formulas, and an arrow (→) separates the reactant and product (left and right)...
01:20Chemical Equilibria: Redefining Equilibrium Constant
The effect of an inert salt on the solubility of a sparingly soluble salt is known as the salt effect. The degree of the salt effect varies with the ionic strength of the solution, which in turn depends on the activity of the species in the solution. The activity is expressed as the product of concentration and the activity coefficient of the species.
To calculate the equilibrium constants of solutions of moderately high ionic strength, one must account for the salt effect. This redefined...
To calculate the equilibrium constants of solutions of moderately high ionic strength, one must account for the salt effect. This redefined...
02:46Calculating the Equilibrium Constant
The equilibrium constant for a reaction is calculated from the equilibrium concentrations (or pressures) of its reactants and products. If these concentrations are known, the calculation simply involves their substitution into the Kc expression.
For example, gaseous nitrogen dioxide forms dinitrogen tetroxide according to this equation:
For example, gaseous nitrogen dioxide forms dinitrogen tetroxide according to this equation:
02:26Chemical Reactions
A balanced chemical equation provides the information of chemical formulas of the reactants and products involved in the chemical change. A reaction’s stoichiometry helps predict how much of the reactant is needed to produce the desired amount of product, or in some cases, how much product will be formed from a specific amount of the reactant.
The relative amounts of reactants and products represented in a balanced chemical equation are often referred to as stoichiometric amounts. However, in...
The relative amounts of reactants and products represented in a balanced chemical equation are often referred to as stoichiometric amounts. However, in...