An Investigation into Senior High School Students’ Understanding and Difficulties in Writing Chemical Formulae of Inorganic Compounds

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.