Frequently Asked Questions About the Worksheet

Q. What is the latest version of the Worksheet?

A. The latest Worksheet is version 1.9, released on April 6, 2007, which you can download now, using the link at page bottom.

Q. What recent changes have you made to the Worksheet?

A. The newest version, 1.7, released in February 2006, contains 50-100 edits to general descriptions and case history information. We also made a few edits to assignment of the reactive groups, and changed the wording for several hazard statements in the Compatibility Chart.

Version 1.6, released in November 2004, contained about 200 new chemicals with new case history information. We also added data from experiments conducted at Argonne National Laboratory on the rates of reaction of about 50 "water reactive" substances. At this time, we discontinued the download option that allowed users to copy a version onto diskettes.

Version 1.5, released in July 2002, contained new case history information in the "Chemical Profile" field, and we corrected formatting in the general description field, edited synonyms, and edited Chemical Abstract Service numbers. We also discontinued the version of the Worksheet for Windows 3.1.

In early 2001, when we released version 1.4, we added 2,500 new chemicals to the Worksheet's database. At that time, we also added chemical profiles and information about water reactivity for those new chemicals, along with new case study information about many of the chemicals in the Worksheet and information about the products that could be generated during some kinds of reactions.

Q. Is there a way to include air or water as one of the chemicals in the Mixture Worksheet?

A. Air and water aren't included in our database of hazardous chemicals, so you can't add them to the "mixture" of chemicals in order to learn whether a chemical reacts with either. But you can find out about air and water reactivity in other ways:

1. When you select a chemical, check its chemical information card for special warnings in the "Special Hazards" area. These special reactivity warnings, in red text, include air and water reactivity (shown as "Air-Reactive" and "Water-Reactive").
   
2. Check the "Air & Water Reactions" section, under the "Response Information" tab, for more details about the air and/or water reactivity of the chemical.
   
3. Click the "Additional Information" tab to check the "Chemical Profile" section for an even more detailed overview of the chemical's reactivity.
   
4. In the Mixture Worksheet, check the Hazards Statement (in the lower scrolling box) for the "Special Hazards of Each Chemical" section. Air and Water reactivity information is displayed in this section.
   
5. Whenever you print out the results of mixing chemicals on the Mixture Worksheet, we encourage you to also print out the chemical information card for each chemical as well. To do that, in the Mixture Worksheet, click on the name of each chemical in the upper box, click "Info on Selection" to view the information card for that chemical, then press the printer icon in the upper right corner of the card to print the card.

Many people have asked to be able to add air or water to the mixture. We are reviewing the Worksheet's design to see if there's a better way to present air and water reactivity.

Q. I used the Worksheet to "mix" some chemicals together. It predicted "No reaction expected." Should I trust this prediction?

A. We believe that the Worksheet accurately predicts whether or not a reaction will occur between two chemicals that you select. But sometimes, there's more to the story. For instance, to predict the reactivity of a mixture of more than two chemicals, the Worksheet predicts the reactivity between all possible pairs of those chemicals. But sometimes, three or more chemicals can react together in ways the Worksheet can't predict. In some cases, for example, a chemical may catalyze (speed up) the reaction between two other chemicals, making that reaction more violent than the Worksheet would predict.

Here's another example: if you mix lithium aluminum hydride with an ether, such as diethylene glycol dimethyl ether (DGD), the Worksheet will correctly predict no reaction between those two chemicals. But there are two other potential hazards associated with this mixture:

• Over time, ethers such as DGD can combine with atmospheric oxygen to form peroxides. These peroxides can combine explosively with lithium aluminum hydride.
  
• If the ether contains water, the lithium aluminum hydroxide and water can react?in a potentially violent manner?to form hydrogen.

The Worksheet alerts you to both these hazards, but you need to check the information it shows you about each chemical?not just the information on the Mixture Worksheet?to see this. (To see the information about a chemical in your mixture, from the Mixture Worksheet, click on the name of that chemical, then click Info on Selection.) Check "Additional Information" about DGD to see that DGD reacts with oxygen to form peroxides, and check "Special Hazards" and "Air and Water Reactions" for lithium aluminum hydride to see that it's a water-reactive chemical that can react violently with water to generate hydrogen.

Q. When I combined nitric acid and sodium hydrosulfide, one of the hazard statements was "flammable gas generation." Can the Worksheet tell me what flammable gases could be expected?

A. In this case, yes, but this version of the Worksheet provides this information only for some chemicals. You won't see this information on the Mixture Worksheet (where you see hazard statements for the mixture), but sometimes you can find it by selecting the name of each chemical in the mixture, then clicking Info on Selection. For example, by doing this, you can see that sodium hydrosulfide mixed with an acid generates flammable hydrogen sulfide vapors.

Q. What are "reactive groups"? I've never heard that term before.

A. To develop the Worksheet, we assigned each chemical in its database to one or more reactive groups. These are categories of chemicals that react in similar ways because they are similar in their chemical structure (to see descriptions of all the reactive groups we defined, from the Mixture Worksheet, click Reactive Groups). To predict the reactivity of a mixture of chemicals, the Worksheet first identifies the reactive groups to which the chemicals belong, and then predicts the kinds of reactivity likely to occur when members of these groups are mixed together. You can add reactive groups as well as specific chemicals to a mixture (and you may want to do this if you know, for example, that a substance is, say, a base, but don't know its name or CAS (Chemical Abstracts Service) registry number). (To add a reactive group to a mixture, from the Mixture Worksheet, click Reactive Groups, click the name of the group you want to add, then click Add Selected Group to the Mixture.)

Q. Can I add as many chemicals as I want to a mixture?

A. The Worksheet does not place any set limit on the number of chemicals in a mixture, but its calculations tend to bog down if you add more than about 15 chemicals.

Q. Does the Worksheet have any bugs?

A. Here are the known bugs in the current version of the Reactivity Worksheet:

1. Mixture save files are not compatible with new versions of the Worksheet. If you saved mixtures in version 1.5, the save file will not work properly in version 1.7. Unfortunately, you must recreate the mixtures. Also, note that the database of chemicals changes between versions. Some chemicals may no longer be in the database and some mixture results may change.
   
2. Some Windows users have experienced printing problems. To work around this problem, press the Print button, then click Save to save your work as a text file; you then can print the text file normally.
   
3. Some Windows users have reported background colors changing to black and white or other color combinations while the program is running. The colors return to normal once you exit the program.

Bugs in earlier versions: A bug in version 1.3. (released in January 2001) caused incorrect hazard statements to appear in the Compatibility Chart (a new feature not in version 1.2). This bug was fixed in version 1.4 (released in March 2001).

Q. Is there a way I can add more chemicals to the Worksheet's database or make other modifications to the Worksheet?

A. We've written up a brief technical document to answer this question. See the link, Modifying the Chemical Reactivity Worksheet, at the bottom of the page.

Q. Do we need to obtain either individual or site licenses to use the Worksheet?

A. The Worksheet runs in the Oracle Media Objects (OMO) Player, a commercial application. Both the Player and Worksheet may be freely distributed at no charge.

Q. Can we run the Worksheet from our server?

A. The Oracle Media Objects Player was not designed to run over a server, so we recommend that you install the Worksheet on each user's machine (the Player is automatically installed when you run the Worksheet installer).

Q. Is the Windows version a 16-bit or 32-bit application?

A. The Oracle Media Objects Player is a 16-bit application. It runs in Windows 3.1 as well as in Windows 95, 98, NT, 2000, and XP.

Q. My company has decided to adopt 32-bit compliance for the software used by its employees. Can you provide us a full 32-bit version of the Worksheet so we can continue to use it?

A. We developed the Reactivity Worksheet in the Oracle Media Objects Environment, and it runs within the OMO Player, which dictates that the program is 16-bit. Oracle has no plans at this time to put out a new version of OMO, so the Worksheet will remain 16-bit for a while longer?sorry. We have developed a new version of the Chemical Reactivity Worksheet in Filemaker Pro, a 32-bit application. This version is available as a small part of a large software application known as CAMEO (Computer-Aided Management of Emergency Operations) (see link below).

Q. What kind of software is the Worksheet?

A. The Chemical Reactivity Worksheet ("reactive.sta" and supporting files) is an Oracle Media Objects "stack" (much like a HyperCard stack) that runs on Macintosh computers and in Microsoft Windows 95, 98, NT, 2000, and XP. To run, it needs the runtime application "OMOPlayer" (on a Macintosh) or "Omoplay.exe" (in Windows) and supporting files, which are all distributed with the Worksheet.

Credits

The Worksheet was developed by the Chemical Reactivity Team at the Office of Response and Restoration (OR&R), National Ocean Service, NOAA.

For more information

Chemical Reactivity Worksheet Specialist Direct comments or questions about the Worksheet to our Chemical Reactivity Worksheet Specialist.

CAMEO, ALOHA, and MARPLOT The Computer-Aided Management of Emergency Operations (CAMEO) program is an integrated set of software modules designed to help first responders and emergency planners plan for and quickly respond to chemical accidents.

Other pages in this series

The Chemical Reactivity Worksheet The main Worksheet page.

Introduction to the Chemical Reactivity Worksheet How the Worksheet was developed, and how it works.

Downloading, Installing, and Running the CRW Instructions for getting a Windows or Macintosh version of the Worksheet.

Frequently Asked Questions About the Worksheet [Current page]

A Reactivity Example Problem Basic instructions for running the Worksheet.

A Reactivity Problem Set A set of practice exercises.

Tips for Worksheet Users Some tips on how to use the Worksheet effectively.

Modifying the Chemical Reactivity Worksheet A technical document that describes how to add more chemicals to the Worksheet's database or make other modifications to it.