Introduction Stoichiometry is one of the major concepts in chemistry. Conceptual understanding in stoichiometry is crucial for any student taking chemistry as a subject as many areas in chemistry are highly related to this conceptual understanding. Many previous researches found out that students poses a very low conceptual understanding and they also poses many alternative conception related to stoichiometry. Dahsah. C; Coll. R. K (2007), found that students conceptual understanding seem to be related with their ability to solve numerical problem in stoichiometry. Problem solving strategies used by students could indicate the alternative conceptions possessed by them and also their ability to solve a problem. Students need a proper conceptual understanding in order to develop meaningful thinking ability, use and apply that understanding in meaningful ways, (Roth, 1990). However, students seem to be lacking when it comes to conceptual understanding and often resort to rote learning whereby they simply memories certain problem solving methods to answer exam questions. Researchers also found that some high achievers tend to solve numerical problems in stoichiometry based on memorization rather than reasoning, out of proper conceptual understanding (Tóth. Z and Sebestyén. A, 2009). The ability to solve problem successfully does not indicate deep conceptual understanding and these students will stumble when they are exposed to problems which are little bit different from the usual one as they cannot figure out the solution although it is still based on the same concept. Therefore it is essential to get the concept first before anything. Fach. M, Boer. T and Parchman . I (2006) stated that many researchers think that concepts are very difficult to understand. They also found a strong connection between sound conceptual understanding and the ability in
Introduction Stoichiometry is one of the major concepts in chemistry. Conceptual understanding in stoichiometry is crucial for any student taking chemistry as a subject as many areas in chemistry are highly related to this conceptual understanding. Many previous researches found out that students poses a very low conceptual understanding and they also poses many alternative conception related to stoichiometry. Dahsah. C; Coll. R. K (2007), found that students conceptual understanding seem to be related with their ability to solve numerical problem in stoichiometry. Problem solving strategies used by students could indicate the alternative conceptions possessed by them and also their ability to solve a problem. Students need a proper conceptual understanding in order to develop meaningful thinking ability, use and apply that understanding in meaningful ways, (Roth, 1990). However, students seem to be lacking when it comes to conceptual understanding and often resort to rote learning whereby they simply memories certain problem solving methods to answer exam questions. Researchers also found that some high achievers tend to solve numerical problems in stoichiometry based on memorization rather than reasoning, out of proper conceptual understanding (Tóth. Z and Sebestyén. A, 2009). The ability to solve problem successfully does not indicate deep conceptual understanding and these students will stumble when they are exposed to problems which are little bit different from the usual one as they cannot figure out the solution although it is still based on the same concept. Therefore it is essential to get the concept first before anything. Fach. M, Boer. T and Parchman . I (2006) stated that many researchers think that concepts are very difficult to understand. They also found a strong connection between sound conceptual understanding and the ability in