The set of software packages is designed so that each individual product acts as a module of a common CheMentor program. CheMentor is a HyperCard application and the modules are HyperCard stacks. Each section of the practice items explains what types of exercises are available and what students must know to successfully handle the exercises.
Help is available in several different forms.
For example, in the oxidation numbers section, one problem asks for the oxidation number of carbon in CO 2 . The available help is always appropriate to the current section. The feedback may be minimal in some cases, such as in the oxidation number example where the answer is judged correct or incorrect, or more extensive, as in the case of writing formulas for ions where the feedback points to the part of the formula that is incorrect. Calculating Chemical Formulae offers over 75 different problems in which students determine chemical formulas from various types of data including percentage composition, mass composition, synthesis data, combustion analysis, and dehydration analysis as well as combinations of data. When a student does not know how to arrive at an answer, help is again available in several forms.