The guidelines below explain how a student answer is evaluated against a coded correct or incorrect chemical formula or expression answer. You can edit or create this kinds of chemical answers using the Simple Editor.
is equivalent to 
.
is not equivalent to 
.
is NOT equivalent to the isotope template 
. Correct/specific incorrect answers:
A correct/specific incorrect answer may consist of: a single chemical symbol/formula, multiple chemical symbols/formulas connected by "+" signs, or a complete chemical equation.
Correct and specific incorrect answers are not limited to contain valid chemical symbols. For example, an author may script an answer involving the chemical "X" as a placeholder.
State marker: A state marker in a subscript is equivalent to a state marker that is not subscripted. Thus, the following are equivalent:
and 
and 
and 
(difference is slight but look at center of overbar to see that in second example it is centered over the nu and subscript while in the first example it is only over the nu). The following are considered equivalent (with and without the subscript 'e'):
.Particles and mass/charge prefixed particles: The following particles and mass/charge prefixed particles are NOT considered equivalent:
or 
to be marked correct, you will have to code both expressions as alternate correct answers. You should not code for every possible combination of particle and mass/charge particle notation. Good form dictates that a student should use all one type of notation.