The long and complex history to define the composition of water as H₂O is summarized. This case study could be useful not only to introduce the history of chemistry in the classroom but also to teach the basic tenets of the nature of science (NOS). Water has been present in several turning points in the history of chemistry such as the first steps of pneumatic chemistry, the chemical revolution, the beginning of the atomic theory, early electrochemistry, and the theory of ionic dissociation. The human dimension of science has been chosen as one of the numerous possibilities offered by the water case study to teach NOS. For this purpose, topics involved in the history of water such as Van Helmont’s “tree experiment”, the “water controversy”, the revival of Avogadro’s hypothesis by Cannizaro, some scientific highlights of Arrhenius and Laurent, and the identification of oxygen are analyzed.

中文翻译：

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从水到H ₂ O：利用科学的人文维度来教授科学的本质

将水的成分定义为H ₂的漫长而复杂的历史O总结。此案例研究不仅可以在课堂上介绍化学的历史，而且可以教授科学本质（NOS）的基本原理。在化学史上，水已经出现在几个转折点上，例如气动化学的第一步，化学革命，原子理论的开端，早期的电化学和离子离解理论。水的案例研究为NOS的教学提供了众多可能性之一，因此选择了人文科学。为此，分析了水历史中涉及的主题，例如范·海尔蒙特（Van Helmont）的“树实验”，“水争议”，坎尼扎罗（Cannizaro）对阿伏加德罗（Avogadro）假说的复兴，阿伦尼乌斯（Arrhenius）和洛朗（Laurent）的一些科学亮点以及氧气的鉴定。