COMPARISON OF D1AGRAi\IS AND i\10DELS lISED FOR TEACIIING ATOl\lIC OIWITJ\LS IN TilE SENIOR SECONDARY SCIIOOL

ABSTRACT

This thesis is a report on a comparative study of diagrams and models

used as teaching aids in teaching atomic orbitals in senior secondary schools

(SSS). An orbital represents a three-dimensional ,volume of space around an

atomic nucleus, where electrons arc found. Diagrams of orbitals in textbooks and

on teachers' chalkboards appear in two dimensions, making visualization difficult

for students.

Three second-year elective chemistry classes in different schools in the

Cape Coast Municipality were pretested on atomic orbitals. They were then

taught the concept of atomic orbital, using diagrams only, models only, and a

combination of diagrams and models respectively as teaching aids. Finally, they

were posttest on the concept.

Analysis of covariance (ANCOVA) on the posttest scores of the students,

using their pretest scores as covariate, ranked the teaching aids in the order:

"models only", "diagrams and models" and "diagrams only". A McNamara chi-square

test on changes in students' misconceptions from the pretest to the posttest

showed that the "models only" class had the highest significant proportional c

decrease in misconceptions, whilst the "diagrams only" class had the least.

It is therefore concluded that the use of models only as teaching aids is

more effective than the use of diagrams only in enhancing SSS students'

visualization of atomic orbitals. Moreover, combination of diagrams and models

confuses students and hampers their visualization. Suggestions have therefore

been made in the thesis for appropriate bodies to emphasize the use of model in

teaching atomic orbitals to SSS students.