One of my first steps and explorations into chemistry education research involved creating a diagnostic test to use with 1st year students in the chemistry module on both the Pharmacy and Pharmaceutical Science programmes. This approach was previously published in New Directions (see here) and consisted of 40 questions on fundamental chemistry principles pertaining to organic chemistry and basic chemistry knowledge that 1st year students on our programmes should have acquired based on the entry requirements for both programmes. One of the questions yielded unexpected outcomes with both 1st year and 3rd year students when the diagnostic test was piloted and this outcome has been consistently replicated annually with 1st year students!
The question I am referring to is
“Draw the chemical structure of an amide bond”
In the published pilot of the diagnostic test, this question was poorly answered with 80% of the answers incorrect. What has been observed each year the diagnostic test is administered is a similar result, students do attempt to answer the question, recognise there is a nitrogen but are unable to recall correctly the chemical structure of an amide bond. Many draw an amine bond. Other functional groups feature in the diagnostic test with questions that focus on the recognition of functional groups not on drawing them. These questions have higher percentages of correct answers. This year I included a question that required recognition of an amide bond from a selection of four chemical structures. Not surprisingly, a higher number of answers were correct for the question – 58%.
Figure 1. A question on the recognition of the amide functional group
There is something about correctly drawing the structure from visual memory that is causing difficulties. My hunch is that the problem lies in the input approach used by students for this type of information and the manner in which it is studied. Visual memories in humans is exceptionally good however exposure does not lead to enhanced memory which has been demonstrated by the classic penny experiment, locating the nearest fire extinguisher and more recently (which is my favourite) the Apple logo (see article here). This explicit memory or intentional retrieval of encountered events is poor for daily interactions with objects. Constant exposure and interaction however does not lead to accurate spatial recall.
The Apple logo experiment is a repeat of the classic penny experiment where participants were asked to recall the logo from memory and recognise the logo from a set of alternatives. They also measured metamemory judgements to assess confidence either before or after drawing the logo from memory with users rating on a 10-point scale their level of confidence.
Figure 2. An example of some stimuli used in the recognition task (the correct logo is not shown here!)
In general, the participants (85 undergraduate students) were not able to draw the logo from memory. One participant drew it perfectly and seven participants had 3 or fewer errors. In terms of recognition, less than half (47%) correctly recognised the correct logo. There was an advantage with apple users over non-apple users but the difference was not significant. Not surprisingly, the confidence of participants (26 students) was higher prior to recalling the Apple logo (M 8.58) and dropped (to M 5.54) after the retrieval process.
Ok so recalling the amide bond requires conscious thought and for many students it has associations with a nitrogen but they cannot correctly recall the chemical structure. I do emphasise in my diagnostic test feedback, notice the word amide contains a D for double bond as a cue to help them trigger this recall. How many students test themselves when studying or are they rereading their lecture notes with an increased familiarity and hence confidence with such repetition!