By providing detailed information about ions, this program allows the user to calculate the formula for any one of over 7,000 different compounds using a list of 136 positive and 53 negative ions. As well as calculating the formula, the computer displays information about each ion and about the compound calculated.

When the program has loaded, the menu provides the following options: Calculate a formula: Display data on a positive or negative ion; List or print ions held on file and Use the periodic table. This is a data retrieval type of program allowing access to a large amount of information. If, for instance, the first option on the menu is selected, the following informations is given: the name and formula of the compound; the name, number, symbol, valency, and RAM/RMM of the positive/negative ion; the RMM of the compound together with its percentage content of positive and negative ions. An extremely comprehensive booklet accompanies the program giving detailed instructions on its use and information on chemical formulae. A useful glossary of chemical terms is also included.

A vast amount of data can be accessed in this program, though it seems to me that its appeal will be very limited. It is obviously aimed at the serious student of chemistry, particularly O and A level pupils as well as college students. Its main advantage, of course, is that all the necessary information about the ions has been brought together, so that the student does not have to research the information for himself in books, before being able to calculate the formulae

Control Keys: kept to a minimum. The program is menu-driven, so that the pressing of any key highlights the option chosen, while 0 confirms the choice
Keyboard play: very fast
Use of colour: good
Graphics: hardly any