2.5.2 Pattern match with JME
The Question stem, Default mark and General feedback sections are as usual.
1,2-Difluoroethene has the formula CHF=CHF. Stereochemically there are two possibilities E and Z.
Z-difluoroethene and E-difluoroethene
With stereochemistry turned on the JME will return F/C=C\F for the Z isomer and F/C=C/F for the E isomer.
Please be aware that the ‘\’ character is the ‘escape’ character in the pattern match algorithm that enables ‘special characters’ to be matched. For example match(\|) will match ‘|’. Consequently in the response match for Z-difluoroethene the ‘\’ character is used to ‘escape’ itself and the response match must be written as match(F/C=C\\F).
Answer: The first answer must be the SMILES string for the correct answer as this is used as the basis for the Atom count feedback. In this case the correct answer for acetic acid is ‘CC(=O)O’. Please note that brackets are special characters that have to be ‘escaped’ as shown in the example.
Grade: Between ‘none’ and 100%. At least one response must have a mark of 100%.
Feedback: Specific feedback that is provided to anyone whose response is matched by the response matching rule in Answer.
Atom count feedback: If this is ticked the system generates feedback based on a comparison of the student’s response and the correct answer given in Answer 1
The feedback for all non-matched responses should go into the ‘Any other answer’ field.
Atom count feedback: The student’s response is compared against the correct answer given in ‘Answer 1’ and feedback is generated on the atoms that are in both the student’s response and in the correct answer
The resulting question when run in 'interactive with multiple tries' style looks as follows:
The student draws their response using the tools provided by the JME.
Pattern match with JME questions are not accessible to totally blind students or to students who are unable to use the pointer.