Secondary 1 – Chemistry : Chemical Reactions
Secondary one students were learning a new chapter about “Chemical reactions.” They learned that changes in matter are divided into physical and chemical changes. They were curious, was there any chemical reaction in the chemical change? Or was there any chemical reaction in the physical change? Based on this curiosity, they conducted experiments in the laboratory to observe and analyze the differences between physical and chemical changes and identify the indicators of chemical reactions.
In the first experiment, Students observed two solutions, A and B containing a mixture of water and food coloring. In cup A, they added 20 ml of water and found out it was just a normal mixture, and no chemical reaction happened. Hence they could readily classify it as a physical change. Meanwhile, they added a few drops of sodium hypochlorite to cup B and stirred it slowly. They observed the color turned colorless, and it was irreversible. They deduced it as a chemical change because a chemical reaction happened.
In the second experiment, they observed and analyzed the chemical reaction between acetic acid and sodium bicarbonate. From this experiment, they found out some indicators of chemical reaction such as gas produced, change in color, change in odor, change in temperature, and new products were formed. Students were excited about the activity and looked forward to the next experiment. Good job, Secondary-1. ***
