Primary 6 – Science: Invisible Message Experiment
Primary 6 students learned about chemical reaction in Science class. Chemical reaction involves substances that react together to form one or more new substances. Here, the substances that react together are called by ‘reactants’, while the new products formed from the reaction are called by ‘products’. There are several signs of chemical reaction that we can observe, they are the production of gas, appearance of bubbles, the change of colour and temperature of the substances. To prove that chemical reactions happened, P6 students had and experiment about “Invisible Message”. In this experiment, students wrote a message with invisible ink and their friends needed to figure out the message using Science.
First, students prepared the invisible ink made of water and baking soda. They needed to dissolve the baking soda into the water and mixed it evenly. After that, students carefully dipped their brush or cotton bud into the mixture and write the message on a piece of paper. This step had to be done carefully since students couldn’t revise their writing. After few minutes, the messages on the paper disappeared as the ink dried. To make the activity more exciting, students exchanged their secret messages to other friends in the class and they needed to figure out the message in the paper.
Here was the magic, students made a solution of hand sanitizer and turmeric powder to reveal the message. This solution created yellow colour got from the turmeric powder, but if it passed through the message, it could turn red. Students carefully brushed this solution on the paper, revealing the secret message little by little. They felt amaze with this step since the message could appear with red ink, when in fact they didn’t use red paint at all.
From this experiment, students learned that change in colour is one of the signs happened in chemical reaction. When water and baking soda reacts with hand sanitizer and turmeric powder, the red colour will appear. By having this activity, students did not only prove that chemical reactions happen between two or more substances, but they also proved that they could make an exciting and fun activity using Science.
Learning about chemical reactions can bring some advantages for the students. First, it can raise student’s awareness in understanding the world around them. Without them realizing it, chemical reactions happen in our daily life, for example baking, cleaning and even our digestion process. By learning this material, they can be aware of the phenomena they meet daily. Second, it can help students in developing their critical and logical thinking. When students analyse a chemical reaction, they need to observe, predict the result, connect their experience with the reactions and make conclusion. Last, it hopefully can spark student’s interest in Science. The change in colour, temperature and the appearance of bubbles may pique students’ curiosity that leads them in learning Science more.
