This study investigated the effectiveness of using laboratory experiments and demonstration methods to teach solubility and solubility product to high school students in Medan, Indonesia. The results showed that using innovated laboratory experiments increased student achievement more than conventional teaching methods, with achievement increases of 109% versus 104%. However, using innovated demonstration methods resulted in lower achievement increases compared to conventional methods, at 104% versus 135%. Student motivation was also found to be positively correlated with achievement when using innovated teaching methods. The study concludes that chemistry teachers should use laboratory experiments when teaching solubility and solubility product as it leads to higher student achievement and interest compared to only conventional methods.

1. Innovation Of Laboratory Experiment and Demonstration Method to Increase Student’s
Achievement in Teaching of Solubility and Solubility Product
Manihar Situmorang, and Dina Adreini Br. Tarigan, School of Chemistry FMIPA Unimed
Jurusan Kimia FMIPA, Universitas Negeri Medan, Jl. Willem Iskandar Pasar V Medan 20221, E-mail
Dina_Adreini@yahoo.co.id
ABSTRAK
The purposes of the study are to investigate the effectiveness of laboratory experiment to
increase student’s achievement in teaching of solubility and solubility product to investigate the
effectiveness of demonstration method with inquiry approach on the teaching of solubility and
solubility product, and to obtain the method on the teaching of solubility and solubility product
in order the student could achieve the highest communication on the teaching and learning
process. The research was carried out experimentally by teaching senior high school students
(SHS) using of a set of innovated laboratory experiment compare with conventional method on
chemistry topics of solubility and solubility product. The population of this research was the
second year SHS of three different schools in Medan. The sample is selected by using purposive
sampling to choose two classes in every school where one is treated as experimental class and
another is as a control class. The selected samples in every class were grouped based on their
achievement on chemistry in the first semester to make them in to two categories, the relative
high achievement (HA) and relative low achievement (LA). Experimental class is tough by
using innovated laboratory experiment while the control class is tough by using conventional
method. The data were collected by using a set of multiple test that covering all subjects being
taught. The effectiveness of the teaching method onto the student’s achievement in teaching is
obtained from their ability to answer the question before teaching (pre-test), and after learning
process have been conducted (pos-test).
The affectivity of Laboratory experiment (109%) is found higher than that with the
conventional methods (104%). The innovated demonstration on the teaching of solubility and
solubility product is find effective to increase the student’s achievement on chemistry subject,
where the students achievement on chemistry by using modified Laboratory Practicum
(M=66.61±5.50) is found higher than that by using conventional Method (M=50.47±9.21), and
the two method are significantly different, t-tes was found at 5.712 > ttable 1.990. However, the
affectivity of innovated Demonstration Method (104%) is lower than that with the conventional
methods (135%). The results has sowed that the students achievement on chemistry by using
modified Laboratory Practicum (M=70.22±5.63) is found higher than that by using innovated
Demonstration Method (M=66.61±5.50), t-tes was tcount 6.123 > ttable 1.990. The affectivities of
Laboratory experiment (109%) is higher than that with the Demonstration methods (104%). The
student’s motivation is positively correlated to student’s achievement on the teaching of
chemistry topic of solubility and solubility product (r2=0,891). Increasing the student’s
achievement in chemistry subject is related to their motivation in learning process as results
from the innovated teaching method.
It is suggested to chemistry teachers to use laboratory experiment in teaching of solubility
and solubility product because able to increase student’s achievement and will give more
interest impression learning than conventional only and also effective in increasing their
achievement. A school holder has to provide and to facilitate the laboratory equipment in their
school to be used in teaching and learning of chemistry.