Titration: It is a chemical experiment in which the concentration of one solution is found by adding a little bit of another solution, finding the point at which the reaction ends, and calculating from that.

Core Competency Reflection: I felt all kinds of joy and sorrow while doing the Lab 20C experiment with my friend Peter Han. I felt the emptiness that comes from making mistakes in the experiment, and the happiness and satisfaction when I found the right value. Through this process, I grew more and was able to prepare perfectly for the remaining journey, especially the journey to finish Chemistry 12. In fact, since I had never done a proper chemistry experiment in Korea, this experience was a new stimulus for me. It was a very impressive experience for me to see the color change to pink when the two solutions were mixed and reached the critical point.