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Chemical Reaction and Equilibrium Software
HSC Chemistry is the world's favorite thermochemical software. HSC is designed for various kinds of chemical reactions and equilibria calculations. The current version contains fourteen calculation modules displayed as fourteen options in the HSC main menu:
1. Reaction Equations
2. Heat and Material Balances
3. Heat Loss Calculations
4. Equilibrium Compositions
5. Electrochemical Equilibria
6. Formula Weights
7. Eh - pH - Diagrams
8. H, S, C and G Diagrams
9. Phase Stability Diagrams
10. Mineralogy Iterations
11. Composition Conversions
12. Elements
13. Water (Steam Tables)
14. Units
The objective of HSC is to make conventional thermodynamic calculations fast and easy to carry out using personal computers. Therefore HSC has a wide range of application possibilities in scientific education, industry and research. Thermochemical calculations are useful, for example, when developing new chemical processes and improving old ones. HSC Chemistry is also a useful tool for universities and schools in chemical practicals and studies.
Traditionally, thermodynamic calculations based on experimental or assessed data have utilized stability functions in various thermodynamic data books and papers in scientific journals. The difficult searching stage and complicated calculations, as well as inconsistencies arising from different selections of standard and reference states, have made this calculation procedure quite time-consuming.
HSC Chemistry offers powerful calculation methods for studying the effects of different variables on the chemical system at equilibrium. For example, if the user gives the raw materials, amounts and other conditions of almost any chemical process, the program will give the amounts of the product as a result. HSC also makes heat and material balance calculations of different processes much more easily than any manual method. The Eh-pH-diagrams option of HSC also offers a very fast way of studying the dissolution and corrosion behavior of different materials.
Of course, HSC does not solve all chemical problems, because it does not take into account the kinetics (rates) of the chemical reactions and non-ideality of solutions. However, in many cases it is a very inexpensive and useful tool which helps to find the optimum reaction conditions and yields for experimental investigations without expensive trial-and-error chemistry.
Chemical software
Software termochimica
Reazione chimica
Calcoli termodinamica
Equilibrio chimico
1. Database fixes:
• HSC now finds all the F- and Zr- containing species.
• Database Editor bug which sometimes created empty records fixed.
• CrS1.333 H 37.3 -> -37.3 kcal/mol (Typo in HSC database, Mills 74).
• HOI(g) -> HIO: Reliability Class 1 -> 5 (Gas in Pankratz 95 ?).
Compare to HIO(g)(Cor 90, Landolt 01).
• I(-3a) -> I3(-a) (Typo in HSC database, Fabricius 94).
• MoF2 too stable: Reliability Class 2 -> 5 (Ruzinov 75).
• PbSO4*PbO was removed (Enthalpy value typo in Bard 85).
• SrZr(Si2O7) was renamed SrZrSi2O7 (Huntelaar 95).
• UO2(G) -> UO3(G): (Typo in HSC database, Phillips 88).
• U3O5 deleted: (Typo in Samsonov 78, data seems to be for U3O8).
• ZrF2 too stable: Reliability Class 1 -> 3 (Barin 77, Glushko 94, Landolt 00)
• Some aqueous (a) species was changed to (ia).
2. Tpp- Module fixes:
• Scale and Print Dialog bug fixed.
• Diagram Area Color Dialog bug fixed.
• Print and Label dialogs with H, S and Cp diagrams.
3. Water Module fixes:
• Fixed: Small changes in Point 1 did not automatically effect the Phase option.
• More density values at higher pressures and temperatures.
4. Equilibrium Module:
• Species selection dialog: Sort mode bug fixed.
• Gibbs-routine fix: Diagram button may be pressed before the calculations are ready without crashing application.
• Pic-routine improvement: Enter -key moves forward after X- and Y-axis species selection.
5. New "Key Word Find" Option in Database Menu finds, for example, all the species which contain the Key Word "benzene".
6. "Key Word Find" may also be used from Database Peep routine.
7. Clearer option captions in Database Menu.
8. More warning dialogs.
• Peep Database dialog: Warning of high number of print pages.
• Element Find Dialog: More Tool Tip Text.
• Lpp module: Improved "Triple Point Outside Range" warning.
9. Several small fixes in Help- and Manual- files.
10. Maximum number of records in HSC databases was increased from 32767 to 2147483647 records.
11. "HSC DLL Tool" opens native HSC functions and database for use in Visual Basic applications and other programming environments.
12. "WNDTLS32.DLL could not be found" error message bug in HSC Help routine was fixed.
13. Heat and Material Balance Module: Stream temperature link refresh bug fixed.
14. Some other small fixes. For example, HSC main menu flicker in some computers was fixed.
Traditionally, researchers have tested their ideas by writing out reaction equations, and then calculated equilibrium constants and heats of reactions from standard thermochemical data. A time-consuming search for this data with standard state conversions was needed, however.
HSC does all the above instantly - you simply type the reaction equation in the input field and HSC gives you the heat of the reactions, equilibrium constant at any temperature and amount of species. HSC even checks the elemental balance and gives potentials vs. the standard hydrogen electrode for electrochemical reactions.
The calculated heat of reaction is the amount of heat that will be absorbed or released in the reaction. The equilibrium constant predicts the direction of the reaction. User input may be in the form of simple formulas or chemical reactions:
Na2SO4
Mg = Mg(g)
2Al + 3/2O2(g) = Al2O3
H2O = 1/2O2(g) + 2H(+a) + 2e-
Ag = Ag(+a) + e-
3NO2(-a) + H(+a) = 2NO(g) + H20 + NO3(-a)
2Al(+3a) + 3S(-2a) + 6H2O = 2Al(OH)3 + 3H2S(g)
Heat balance calculations are needed to estimate the energy requirements and the cost of the process, as well as the operation preconditions. In fact no process will work if the heat balance is not met.
Input and output species, as well as their amounts and temperatures, are needed for the calculations. HSC recalculates the heat balance every time the initial conditions are changed. In this way you can, for example, find the optimum preheating temperature for raw materials to offset electrical heating of reactor system.
Theoretical heat balances can be taking species and amounts from the reaction equations or equilibrium calculations.
Real heat balances can be calculated by taking species and amounts from experimental results.
These balances are very useful when scaling up processes from laboratory to industrial scale.
By pointing and pressing on the appropriate buttons, the user can select either Celsius or Kelvins for temperature, moles or kilograms for amounts and calories or joules for energy units.
The Temp Bal button is used to get product temperature at zero heat balance. In the case of gaseous combustion processes with zero heat exchange to the environment, this yields the adiabatic flame temperature.
Both input and results can be saved as text files by pressing the Save button. This assures the files will be available later for editing in HSC or use in other programs.
Equilibrium calculations offer a practical way to observe the effects of process variables, such as temperature and amounts of raw materials on product composition.
With this program option you can calculate equilibrium composition and amounts of prevailing phases in any reactor. You only specify the raw material amounts, temperatures and the species of the system. These species can be specified by selecting the elements of the system, or typing the formulas, or by editing the old file. Activity coefficients can be given, if necessary, as constants or as functions of temperature and composition.
You can select linear or logarithmic scale and set maximum and minimum values for the x- and y-axis.
The tabular numerical data which is used to draw the diagram can be saved as a normal text files by pressing the Table button. These files can be read, for example, in spreadsheet programs for further calculations.
A special Cell Equilibrium calculation option is also available for calculating charge and composition of phases in electrochemical cells, such as batteries.
The simplest calculation option is a versatile program for calculating formula weights. It accepts any form of chemical formula using conventional organic or inorganic expressions (without superscripts and subscripts).
Typical entries might be:
NaBO3*4H2O, H2(Sn(OH)6), (C2H5)2O, etc.
The program displays the formula weight and elemental composition as both weight and atomic percentages. A paper copy of results is immediately available by pressing the Print button.
Phase stability diagrams offer a quick way to locate the stability regions of different phases at varying partial pressures of oxygen, sulfur, chlorine, nitrogen oxide, etc. The diagrams are quickly constructed in the following steps:
• Select the three elements and press the OK button.
• Select species as well as the x- and y-axis.
• Press the Go to PSD button to see the diagram.
Labels can be relocated with the mouse; scales can be changed by pressing the Menu button; fonts can be changed by pressing the Font button, titles can be edited directly in the title fields.
If you want a paper copy of the diagram press the Print button and you will get a copy at the best resolution of any MS Windows - supported printer.
Knowledge of the stabilities of ionic and non-ionic species in water solutions is critical to understanding problems of corrosion, dissolution, leaching and selective precipitation. This information can be displayed graphically by Eh - Ph - diagrams.
With this calculation option you can easily draw simple diagrams with only element and H2O as well as more complicated diagrams with several elements.
The dotted cyan lines indicate the stability area of water. Stability regions of ions can be outlined with blue lines, if necessary. Concentrations of the elements as well as scale settings can be changed by pressing the Menu button.
High resolution paper copies can be produced by pressing Print BW or Print Col buttons, as with the other calculation options.