The ASTM Computer Program for Chemical Thermodynamic and Energy Release Evaluation CHETAH®, Version 11.0

    Frequently Asked Questions

    What is the correct way to enter a balanced reaction?

    Do not use the count entry on the molecule descriptor grid to balance your equation. The count entry only serves as a counter to the number of groups and not molecules. Use this screen to describe each reactant and product compound or element on the molecular descriptor grid screen. Once this is done, choose the reaction thermochemistry icon. This results in a screen where the user identifies each chemical as a reactant or product. The user also enters the molar stoichiometric coefficients for the reaction. The program will generate an error message if the reaction is not balanced. This process is also demonstrated in the demo section of the web site and is further explained in the user’s manual.

    Can I do an energy release evaluation calculation on an ideal gas molecule?

    Yes. The correlations used for the energy release evaluation are valid for gas, liquid, or solids.

    FAQ computer problems for previous versions:

    The following are known problems that have shown up on some computer systems for CHETAH Version 9.0 only:

    1. I am running the Vista operating system. When I install the program and try to run it, I get an error message related to vsprint.ocs and the program does not run. What do I do?

    After your installation is otherwise finished, please take the additional steps outlined in the Vista Compatibility Guide.

    The following are known problems that have shown up on some computer systems for CHETAH Version 9.0 and earlier.

    2. I get the following error when I try to run SmilesInput: "Put err.dat and other.dat and .txt files in \chetah\ dependency directory". What do I do?

    Create a .dac file by entering a molecule into the Molecular grid and click on File then Save as. Give a file name and save it. Next click on File, then Open, and browse to the file just saved and open it. Now try Smiles Input.

    3. Component 'mscomct2.ocx' or one of its dependencies not correctly registered: a file is missing or invalid. What do I do?

    Step 1: Download mscomct2.ocx and place it under the /Program Files/Chetah/ folder mscomct2.ocx Download Missing File (updated : 05/31/05) Step 2: Click on the "Start" button and then click on Run. Type the following command to register the file: regsvr32 "C:\Program Files\CHETAH\mscomct2.ocx"

    4. "VSPRINT.OCX" is missing. What do I do?

    Some users might need to download the following system file to the Windows/System folder on their computer. VSPRINT.ocx . Users should check with the system administrator for system privileges if the file fails to download successfully.

    Opening a Zip File: If your operating system does not recognize the downloaded zip file then you might need to install WinZip® (or similar software) from in order to run the service pack on your computer. A trial version of the software can be downloaded from

    Stock #: DS51HOL

    ISBN-EB: 978-0-8031-7125-1

    DS51F-C01 DS51F-C02 DS51F-C03 DS51F-C04 DS51F-C05 DS51F-C06 DS51F-C07 DS51F-F01 DS51F-F02 DS51F-R01 DS51F-R02 DS51F-R03 DS51F-SN DS51F DS51F DS51F DS51F DS51F