Dibeng MolWts - Version 1.0 Deluxe Operating Manual

Install the program and run it per the instructions contained in the readme.txt file. After that, follow these instructions to quickly learn the interface of Dibeng MolWts. Every effort has been made to keep this program as intuitive and as user friendly as possible. We try to keep all our programs pretty self-explanatory, but incase you still need help (don't worry, it's not you; the program is very complex), here it is:

1. After starting the program (see Installation Instructions contained in readme.txt) you will be presented with the following program intro screen:

Here you can press F1 (Frmla) to input a chemical formula to be evaluated. Pressing F2 (Vars) will open up the home screen variable loading feature (more on that later). If you wish to see what certain keys do while you are inputting your formula, press F3 (Keys). A key definition list will be displayed and the ENTER key exits that screen. F4 (More) takes you to the next menu screen:

You can now press F1 (HKeys) to enter the hotkeys screen, where you can view and assign your hotkeys (more on this later). F3 (About) displays the program credits and contact information to contact the authors. The same information is also at the bottom of this manual. ENTER exits the about screen as well. F5 (Exit) quits the program. Some sections described above have corresponding sections below. Click on the hyperlinks or scroll down to view each section.

Frmla: Enter a Molecular Formula

After you have decided to enter a molecular formula and have pressed F1 (Frmla), you will be presented with the following prompt:

Typing the Formula
Here is where you start typing in your formula. Initially the program is set to accept numbers from the keyboard (8 instead of M). We chose numbers because in many stoichiometry applications most of the formulas entered will have a coefficient. If you do not want to enter an initial coefficient then press ALPHA to accept letters from the keyboard. Notice how the "Numbers" indicator changes to "Letters". Use the ALPHA button to switch between numbers and letters throughout the entering process. Type numbers in the formula in "Numbers" mode and letters in the formula in "Letters" mode. Continue typing your formula until you reach the end. The program reads the formula CASE-SENSITIVE. Cs (Cesium) is different than CS (Carbon and Sulfur). In order to change case, press the 2nd button. Notice that the "->A" indicator switches to "->a" and back to show what case will be typed next. The case indicator means nothing in "Numbers" mode.

Please note: Due to the already enormous size of this program's code and the weaknesses of the TI Basic programming language for TI-85, this program only handles single number coefficients and multipliers (that was hard enough!). Any coefficients or multipliers greater than one digit will result in an "Unrecognized Symbol" error. The program tries to read the second digit as an element symbol. A program that does handle these may be produced if the demand so arises, however, the program size would be increased greatly if not doubled! For now, if you need to calculate C₁₂, simply type C6C6 or C9C3...you get the idea. It works just as well.

Using Parentheses
You can use parentheses in a formula to indicate subformulas:

Inputting parentheses is the next step. We spent a great deal of time in trying to get the program to evaluate parentheses so we want to make sure you know how to use them. :) Parentheses can be entered in "Numbers" mode. Switch to that mode and press the "(" or, after that, the ")" key to input a set of parentheses. You can put a multiplier on the outside of the parentheses to multiply the whole parenthetical formula (ex. Ca(ClO)₂). The "(Sub)=1" indicator shows that parentheses have been entered and that the calculator will evaluate them. Again, we really want to maintain you parentheses awareness as best we can.

Other Features
Other keys that have some effect while you are at the Enter Molecule screen are:

Calculating the Molar Weight of a Formula
Press ENTER when you are done typing to make the program calculate the formula's molar weight. Once the program has calculated a formula, it will give you the answer and at the bottom, you are presented with two options: Again (F2) and Done (F4). Press Again (F2) to enter another formula, or press Done (F4) to go back to the program intro screen. There you can either exit the program or do something else.

When the calculator gives an answer to a formula the units for the answer are always grams per mole (g/mol). It is also possible to find the atomic weight for a single element by entering the element's symbol as the formula and pressing ENTER. The answer is both the molar weight of the element in grams per mole as well as the atomic weight of the element.

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Vars: Home Variables

In Dibeng MolWts - Version 1.0 Deluxe you have the option of storing the atomic weights of elements to their element symbols so that you can use those symbols as home screen variables. For example, if you did store the atomic weights to the variables, you could go to the home screen and type "Xe." The value of that variable would be the atomic weight of Xenon. If your chemistry instructor asks how much 2 moles of Xenon weigh, you could type "2*Xe" and shout out the answer you see on your screen in grams per mole, faster than anybody else:

After you press F2 (Vars) in the main program intro screen, you will see the following screen:

Loading the Variables
Here you can press F1 (Save) to load the atomic weights to the variables. A "Loading..." message will appear as the loading process is taking place. F3 (Help) displays a reference screen that shows some critical exceptions; we had to work around TI's built in constants and even a function name. Na, Mn, and Lu are the element symbols that were affected. Type NA instead of Na, MN instead of Mn, and you just have to know that Lu=175. (We could not use Lu or LU because there is a TI-BASIC function "LU(.") This is all displayed in the "Help" screen. ENTER exits the "Help" screen. F5 (Done) exits the variables screen and goes back to the intro screen.

Please note: In order for all the home screen variables to be accurate you must exit the program immediately after you load the variables. If you enter a molecular formula or edit your hotkeys after you have loaded the variables some of the variables' values will be changed and will no longer be the true atomic weight for the corresponding element.

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HKeys: Hotkeys

The Hotkeys Menu
After pressing F1 (HKeys) you will be taken to the hotkeys menu where you can view or edit your hotkeys:

At the hotkeys menu, the contents of each hotkey is displayed next to its number. If the contents of the hotkey shows "------------," it means that the hotkey is empty and contains no element symbol or formula. In the above screen shot, all the hotkeys are empty. In the following screen shot, all hotkeys are used:

Editing Hotkeys
In order to assign values to the hotkeys, you can press the corresponding function button for the hotkey to be taken to its edit screen. For example, if I wanted to edit the hotkey directly above that contains the value C₂Ca(ClO)₂ (That's a funny formula; I've never seen that before.), I would press F4 because it corresponds to #4, the number of the hotkey I want to change. After pressing F4, the following screen appears:

This is a conformation screen that acts as a protection against bumping function keys and then having to remember what the value of the hotkey WAS. If you do not want to edit the hotkey, press F2 (Keep) and you will be taken back to the hotkeys menu. If you do want to edit the hotkey press F4 (Change). The following prompt will appear and you can type your new hotkey formula in the exact same way you would type it if you were entering a molecular formula in the Frmla screen:

The same keys and methods apply here as they do there. The only difference is that the EXIT key does not go back to the program intro screen but goes back to the hotkeys menu. Your hotkey value will have already been deleted though, and will show up as empty ("------------") in the hotkeys menu.

When you are Finished; Using Your Hotkeys
After you are done viewing or editing you hotkeys, press F5 (Done) at the hotkeys menu screen. You will be taken back to the main program intro screen. From there you can press F1 (Frmla) and access the values of your hotkeys by pressing the CUSTOM key. You will then see a menu pop up like this one. Notice how the hotkey values are displayed:

Those are the hotkey values from one of the previous screen shots in this document. I didn't bother to change them :) Pressing the corresponding function button (F1-F4) will instantly add the formula contained in the hotkey to your main formula. For example, if I wanted to add NaCl to my main formula I would press F3, because that is the function button corresponding to the hotkey that contains it. If you do not want to use a hotkey, press F5 (Cancl) to cancel the menu, and go back to entering your molecular formula.

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Contact Us

Questions, comments, and bug reports are always welcome, but we cannot guarantee an immediate response. We would love to hear from you, however, so if you wish to e-mail Dibeng Software, our e-mail address is:

dibeng@hotmail.com

and our internet address is:

http://go.to/dibeng

You will find lots of other programs there too, both for calculator and computer. Thank you for using Dibeng Software products.

Manual Generated: 7/14/00