Top part of the window - input fram

Top part of the window - input frame - is where you enter known information about the reactants.

Lower part of the window - output frame - is where you will see results.

Reaction equation is displayed between the frames.

Every column contains information about one substance. Number of columns (and size of the dialog window) can be changed to reflect number of reagents in the reaction. To do so use buttons add reactant >> and add product >> to add substance, or close buttons (in the upper part of the input frame) to remove substance. Note that close buttons are not diplayed if there is only one one product or reactant.

If there are too many reagents and the dialog window doesn't fit on the screen, you may switch to alternate user interface. To do so select Alternate UI from the program View menu, press Ctrl-2 or click button on the toolbar.

To enter substance simply enter its formula into formula edit field. In most cases it is enough to write all symbols, numbers and parentheses without any formatting characters. Sometimes you will have to use extended formula format - for example to enter charges of the ions.

Instead of entering formula you may select the reagent from the database.

Note that while you enter the formula, molar mass of the substance is automatically calculated.

Red question signs preceding formulas in the reaction equation are displayed when the reaction can not be balanced. Program displays messages suggesting what the problem is in the status bar. Remember, that not every equation can be balanced. However, even if the program can't balance equation, you can enter coefficients manually, see below.

Once the reaction can be balanced program displays dark green coefficients in front of reagents. No action is required for that - it is enough to enter correct substances. No reagent column can be left empty.

If you know amount of substance - mass or number of moles - enter it into correct edit field in the input frame. If only one value is entered (and the reaction equation is balanced) output frame contains information about calculated amounts of all reagents. If you enter more than one amount of the substance in the input frame, program checks which of the substances is a limiting reagent. This limiting reagent amount is used for the stoichiometric calculation of values displayed in the output frame. Amount of all reagents being in excess are displayed in red.

If the substance used is in the form of solution, to enter its amount you may use concentration calculator. To do so, click n=CV button in the substance column in the input frame.

If the substance used is a gas, you may use ideal gas calculator to convert known volume to mass/number of moles. Just click pV=nRT button in the substance column in the input frame.

Concentration calculator and ideal gas calculator can be also used to convert known stoichiometric amounts of substances to volumes and/or concentrations. To do so use n=CV or pV=nRT buttons from the appropriate column from the output frame

Clear amounts button removes all entered masses and mole numbers for all reagents, leaving formulas (and coefficients) intact.

It is also possible to enter coefficients manually. To do so, check manual coefficients check box. Alternate user interface dialog pops out and let's you enter coefficients manually.

While in manual mode, you can do stoichiometric calculations as well, using entered coefficients. These doesn't have to be correct. For example, we know that in Solvay process one mole of calcium carbonate yields half mole of sodium carbonate. In manual mode you can enter this reaction:

2CaCO3 -> Na2CO3

and use it for stoichiometric calcuations.

If coefficients are entered manually, they are displayed in blue when reaction is properly balanced, or in red when it is not. Even coefficients equal 1 are displayed, as otherwise they could be not visible at all.