@article{oai:kobe-c.repo.nii.ac.jp:00005815,
 author = {平井, 俊男 and 青田, 鏡広 and 豊島, 瑠菜 and 西川, 輝 and 中山, 頼子 and 中川, 徹夫 and NAKAGAWA, Testuo and HIRAI, Toshio and AOTA, Akihiro and TOYOSHIMA, Runa and NISHIKAWA, Hikaru and NAKAYAMA, Yoriko},
 journal = {神戸女学院大学 教職センター研究紀要, Journal of Center for Teacher Education, Kobe College},
 month = {Mar},
 note = {この研究の目的は、高等学校新学習指導要領で謳われている主体的・対話的で深い学びを生徒に保障するための、一連のマイクロスケール実験の開発である。大阪府立長尾高等学校では、市販の安価な小型電子天秤を用い、化学基礎の教科書の「化学反応の量的関係（炭酸カルシウムと塩酸の反応により、二酸化炭素が生成する）」のマイクロスケール実験を開発してきた。2020年 2月末の新型コロナウイルス感染拡大防止のための全国の学校休校直前に、前述実験の今後の課題である誤差を減らすために、塩酸の計量を検定証印付きメスシリンダーから検定証印付きホールピペットへ変更することが有効かどうかについて検証した。その結果、教科書の実験のマイクロスケール化において、1/8から1/2スケールまでの実験では、0.15％の相対誤差をもつホールピペットを用いて塩酸を測り取る必要がない。つまり、相対誤差が 2.0 ％のメスシリンダーで十分であると判明した。より一層誤差を減らすなら、質量測定の精度を上げる必要がある。しかし、精度が0.01 gである市販の安価な小型電子天秤の使用を前提とした場合、本実験のマイクロスケール化では、メスシリンダーを用いた1/4スケールが最適であると判断した。, The objective of this study is to improve the microscale experiment of stoichiometry in high school, which was developed in a previous work. We tried to reduce the experimental errors of it by active learning. Active learning is a new and key concept of the revised Course of Study defined by the Ministry of Education, Culture, Sports, Science and Technology-Japan in 2018. The improved microscale experiment, which uses small quantities of chemicals, includes the reaction of calcium carbonate with hydrochloric acid to form carbon dioxide. It is a scale-down [1/8 or 1/4] model of the normal scale experiment described in a textbook of “Basic Chemistry” in the Course of Study mentioned above. According to the previous work, it is a research task in the future to reduce the error. Just before closing all the schools of Japan in February 2020, the practice for the science club members, who were one freshperson and three juniors, consisted of six lessons as follows: 1) preparatory guidance, 2) previous work and errors of measuring instruments, 3) hypotheses and plans of microscale experiment to reduce the error, 4) preliminary microscale experiment, 5) and 6) the microscale experiment and discussion. Our hypothesis is that we may minimize the experimental errors by using a volumetric pipette to measure dilute hydrochloric acid instead of a graduated cylinder. We verified the hypothesis by experiment. As a result of the experiments, the following are our new findings. 1) Even if we use a volumetric pipette instead of a graduated cylinder to measure hydrochloric acid, we cannot minimize the errors in the case of 1/8, 1/4 and 1/2 scale experiments. That is why the electronic balance used has the smallest relative error of 4.5 % in the case of 1/2 scale experiment, which is larger than both a relative error of 0.15 % of the pipette and a relative error of 2.0 % of the cylinder. 2) The error in the case of 1/4 scale experiment using a volumetric pipette to measure hydrochloric acid is about the same as using a graduated cylinder. In conclusion, we have found that the best scale-down size is 1/4 for the microscale experiment of stoichiometry using a graduated cylinder, which is good enough for this scale. We are convinced that the microscale experiment works well for active learning in high school chemistry.},
 pages = {27--34},
 title = {高等学校における生徒主体型学習による「化学反応の量的関係」のマイクロスケール実験の開発 Ⅱ},
 volume = {4},
 year = {2021},
 yomi = {ヒライ, トシオ and アオタ, アキヒロ and トヨシマ, ルナ and ニシカワ, ヒカル and ナカヤマ, ヨリコ and ナカガワ, テツオ}
}