“…Also, according to Table 3 is shown that the two classes have the degree of students' conceptual understanding of each item of posttest better than the degree of students' conceptual understanding of each item of the pretest. Therefore, it can be concluded that appropriate chemistry teaching integrated Mahaffys' chemistry tetrahedral representation can increase the mastery of students' chemistry representation levels on the material well, especially sub-microscopic and symbolic levels (Georgiadou & Tsaparlis, 2000;Gulacar et al, 2013;Indriyanti & Barke, 2017;Kapıcı & Savaşcı-Açıkalın, 2015;Rau, Bowman, & Moore, 2017;Schmidt & Jigneus, 2003). The PP model has more students with sound conceptual understanding than the TAPPS model (Arikan et al, 2012;Arıkan & Ünal, 2015;Işik et al, 2011;Land, 2017;Pelczer et al, 2013).…”