Materials:
Potato chips (or other thin snacks)
Cup or bowl, water, salt
Steps:
1 Prepare some potato chips and put them in a cup or bowl.
2. Pour enough water to soak the potato chips.
3. Sprinkle a pinch of salt on the potato chips.
4. Wait for a few minutes and observe the changes of potato chips.
Results: Potato chips will gradually swell and form some bubbles on the surface.
Principle: The expansion of potato chips is caused by the infiltration of water, and salt can accelerate the infiltration. Ions in salt can destroy the cell structure on the surface of potato chips, making it easier for water to enter potato chips. The expanded potato chips, like sponges, can absorb more water and salt, thus forming bubbles.
This experiment can not only help children understand the principle of osmosis, but also arouse their interest in food science and make them explore the mysteries of the world more curiously.
Here are some tips to pay attention to when doing experiments:
1, carefully check the specific process of the experiment to ensure that all steps are correct. Before carrying out the experiment, read and understand the experimental steps in advance to prevent the omission of key steps from affecting the experimental results.
2, carefully observe the experimental process, pay attention to the subtle changes. During the experiment, we should carefully observe and record all the changes, which is helpful to understand the mechanism of the experimental reaction and the correctness of the experimental results.
3, the measurement results should be accurate. When planning to carry out the measurement experiment, use accurate measuring tools (such as balance and volumetric flask) to ensure the accuracy of the results.
4. Keep in mind the safety rules. When doing experiments, don't ignore the safety rules, especially the experiments using chemical reagents. Confirm the experimental conditions and equipment, and pay attention to protection.
5. Check the experimental instructions. The experiment shows that the equipment, method and steps are provided. If the operator is a beginner, it is recommended to follow the instructions, and then gradually try various experimental steps or equipment selected by yourself after getting familiar with them.
6. Explore the application of experiments. When doing experiments, be careful, but at the same time, don't limit your thinking. We should explore the application of each experiment and its connection with related fields, and give full play to your imagination and creativity.