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Chemistry Education 2018 Journal of Organic & Inorganic Chemistry
ISSN: 2472-1123 Page 63
August 27-28, 2018
Zurich, Switzerland
8th Edition of International Conference on
Chemistry Education
and Research
In situ generated fluorescent gold nanoclusters (Au-NCs) are
used for bio-imaging of three human cancer cells, namely,
lung (A549), breast (MCF7), and colon (HCT116), by confocal
microscopy. The amount of Au-NCs in non-cancer cells (WI38 and
MCF10A) is 20–40 times less than those in the corresponding
cancer cells. The presence of a larger amount of glutathione
(GSH) capped Au-NCs in the cancer cell are ascribed to a higher
glutathione level in cancer cells. The Au-NCs exhibit fluorescence
maxima at 490–530 nm inside the cancer cells. The fluorescence
maxima and matrix-assisted laser desorption ionization (MALDI)
mass spectrometry suggest that the fluorescent Au-NCs consist
This article surveys and investigates pre-service chemistry
teachers’ misconceptions in stoichiometry at the symbolic
level, and possible solutions to address those misconceptions.
Students and teachers broadly acknowledge the importance and
difficulty of stoichiometry. Available research, meanwhile, also
broadly acknowledges misconceptions at the symbolic level. In
an effort to investigate associated misunderstandings, and to
search for possible solutions, research was performed in Thai
pre-service teachers. Fourteen Thai pre-service second year
chemistry students participated. Three questions at the symbolic
level of stoichiometry were presented asking students to solve
by written explanation. One-on-one interviews were conducted.
72% of pre-service chemistry teachers were not able to solve the
problems because they had multiple misconceptions such as:
misconceptions about the formula related to chemical bonding;
misconceptionsaboutthechemicalequationand;misconceptions
about the calculations and mathematics. The written testing
and interviews revealed that art of the problem is that a strong
foundation in mathematics and chemistry is important and
related to solving the problem of stoichiometry at the symbolic
level. At a deeper level, the misconceptions appear to relate to the
abstractness of stoichiometry at themolecular level and symbolic
level. To be effective, and meaningful, teachers should apply the
so-called three levels of thinking carefully integrating and linking
the macro, molecular and symbolic levels to teach students in
the classroom. In the process, teachers must initially check the
students’ prior knowledge because students must be able to link
prior knowledge such as how to write chemical formulas, how
to balance chemical equations, and how to do stoichiometric
calculations. In short, what is proposed is a holistic and integrative
approach applying the multiple levels of chemistry with careful
consideration of the students’ prior knowledge.
An analysis of pre-service chemistry teachers misconceptions
in symbolic level of stoichiometry
Butsari Phenglengdi
Chiang Mai University, Thailand
J Org Inorg Chem 2018, Volume 4
DOI: 10.21767/2472-1123-C5-015