It will not be enough to simply explain to the students that many situations we encounter, use and observe in our daily lives are related to physics, chemistry, biology or all three. It is important to show them this relationship concretely. The chemistry laboratory experiments in this book are aimed at the cognitive gains targeted in the learning field of "Matter and Its Nature" in the secondary school science curriculum. Chemistry experiments were arranged according to the order of achievement in the relevant learning area at each grade level. There are also research questions about which cognitive acquisition each experiment belongs to, how the experiment will be done with which materials, the visuals of the experiment and what you want your students to answer at the end of the experimental applications. If you are starting to learn new experiences about chemistry laboratory applications, I recommend you to be sensitive about the laboratory notebook first. In this book, tables are already provided for you to record your data. A laboratory notebook in which you record the data requested from you for each experimental application you experience and take small notes with your own words is important for you to remember the learnings that these activities left you in the future.