Abstract

This paper examined the difficulty level of the test items in an introductory course in Chemistry. It determined the discrimination index and the response pattern on the items from the distribution of the responses among several alternatives .The study design was an ex-post facto, a causal comparative design. The sample size was made up of 800 students selected through random sampling from the population of students who sat for Chemistry 102 in 2008/2009 academic session. A 40-item multiple choice was developed from the course contents of Chemistry 102 by lecturers teaching the course following the table of specification. The 30% upper and 30% lower scores were selected for analysis yielding a total of 442 students. The results revealed that the overall difficulty level of the item was 0.54, the overall discrimination index was 0.32. The result also revealed that Option D was most favored among the options, having 16 respondents. The scores were scattered around the potions to discourage guessing. On the overall, 3 out of the 40 items were rejected as a result of wrong application of keys and structures.