Abstract:
Students’ inability to write correct chemical formulae has for some time been a source of
worry to the West African Examinations Council, the body responsible for organizing
examinations in West Africa. Learning how to write chemical formulae is a vital area for one
to progress in the study of chemistry and it is one of the exercises that give a lot of fascination
and challenge to young chemists starting to learn chemistry. This study probed into the
difficulties students have in writing correct chemical formulae from IUPAC names. The study
used a cross-sectional survey using both quantitative and qualitative methods. The sample
used for the study consisted of 334 SSS 3 elective science students for 2008/2009 academic
year drawn from all the schools that offer elective science in the New Juaben Municipality of
the Eastern Region of Ghana. The instruments used for data collection were achievement test
and interview. Some of the key findings about students’ difficulties in writing chemical
formulae from IUPAC names were: students lack of understanding of the Roman numerals
that are put in brackets of IUPAC names, students difficulty in knowing what valencies are
and the role they play in writing chemical formulae, students inability to write the correct
formulae of some radicals and ions and inability to determine the cations and anions of ionic
compounds and hence inability to combine certain cations and anions to form neutral
compounds due to lack of knowledge about valency.
