Views: 5 Author: Site Editor Publish Time: 2021-11-30 Origin: Site
Have kids ever wondered how all the food you eat is digested? Not only does the acid in the stomach break down food, but many small molecules in the body (called enzymes) also help break down food. Enzymes are special types of proteins that speed up chemical reactions, such as the digestion of food in the stomach. Today, Alpha Science is exploring the properties of enzymes, an amazing organism, with children through a children's chemistry experiments activity to teach them about enzymes. Also, have fun learning special chemistry from this kid's science experiment activity to understand how enzymes help protect the human body from harm.
Alpha Science classroom： Materials needed to explore enzymes
Goggles or protective eyewear
Five teaspoons of detergent
One package of dry yeast
Hydrogen peroxide, 3% (at least 100 ml)
Five 16-ounce disposable plastic cups
A work area that can be wetted (will not be damaged by any spilled peroxide or drinking water)
Food coloring (optional) materials
Alpha Science Classroom： Exploring Enzymes, a step-by-step tutorial
Step 1: First, children take a cup and dissolve the dry yeast in about ½ cup of warm tap water. The water should not be too hot but should be close to body temperature (37 degrees Celsius). Let the dissolved yeast sit for at least 5 minutes.
Step 2: Children mark the remaining four cups from one to four with a permanent marker.
Add a teaspoon of dishwashing detergent to all marked cups. No additional cups are added at this point.
Step 3: Before children use hydrogen peroxide, wear safety goggles for eye protection. If hydrogen peroxide spills, wipe it up with a damp paper towel. If it gets on the skin, be sure to rinse the affected area with plenty of water.
Step 4: Children need to drink two cups with one tablespoon of 3% hydrogen peroxide solution. Use a fresh spoon to hold the hydrogen peroxide.
Step 5: When drinking the third cup, add two tablespoons of hydrogen peroxide. By the fourth cup, add three tablespoons of hydrogen peroxide.
Or, you can add a drop of food coloring to each labeled cup. (You can choose a different color for each one for easy identification)
Step 6: Children pick up cup #1 and place it in the work area in front of them. Using a tablespoon of fresh yeast solution, add a tablespoon of dissolved yeast solution to the cup and shake gently. What happens when you add the yeast? Do you see the reaction taking place?
Step 7: Children place cup #2 in front of you and add a tablespoon of yeast solution to the cup again. When you add the enzyme, does the catalase react with the hydrogen peroxide? Can you see the reaction products being formed?
Step 8: The children add a tablespoon of yeast solution to the third cup. Do you see the same reaction taking place? Are the results different or the same compared to the second cup?
Finally, add a tablespoon of yeast solution to the fourth cup. Do you see more or fewer reaction products compared to the previous results? Can you explain the difference?
Place all four cups side by side in front of you and observe the results. Did the enzyme react in all the cups, or were there exceptions? How do the results look different for each cup? Why do you think this is the case?
Alpha Science Classroom: Exploring Enzymes, Scientific Principles
Alpha Science Classroom tells the children that you may see a lot of bubbles and foam in this activity. What makes the bubbles appear? When the enzyme catalase comes in contact with its substrate, hydrogen peroxide, it begins to break down into water and oxygen. Oxygen is a gas, so it must be expelled from the liquid. However, the detergent you add to all solutions traps the bubbles, which creates a stable foam. As long as enzymes and hydrogen peroxide are present in the solution, the reaction will continue and foam will be produced. Once one of these two compounds is used up, the formation of the product stops. If no detergent is added to the reaction, bubbles are seen, but there is no stable foam.
If there is no hydrogen peroxide, the catalase will not work, which is why you should not see any bubbles or foam in the first cup. The catalase reaction can only occur in the presence of hydrogen peroxide, as you have observed in other cups. In fact, the reaction of catalase depends on the concentration of the substrate. If there is an excess of the enzyme but not enough substrate, the reaction will be limited by the availability of substrate. Once more hydrogen peroxide is added to the solution, the reaction rate increases because more substrate molecules can collide with the enzyme, and more products are formed. The result is that as the amount of H2O2 in the reaction increases, the amount of foam produced in the cup increases. Once you add another tablespoon of hydrogen peroxide to the first cup, you should see more foam, at which point the amount of foam produced should be about the same as in the second cup. However, at some point, you will reach a substrate concentration at which the enzyme will saturate and become the limiting factor. In this case, you will have to add more enzymes to speed up the reaction again.
Many other factors also affect enzyme activity. Most enzymes only work under optimal environmental conditions. If the pH or temperature deviates too much from these conditions, the enzyme reaction will slow down.
The bubbles produced by the magical enzymes and hydrogen peroxide are beautiful and intense, just like the process of food just arriving in our stomachs for digestion. I believe that the alpha science classroom's children's chemistry experiments activity today helped children to learn about the chemical reaction of enzymes and the process of food effect, which is the magic that humans themselves carry? We hope that through this kid's science experiment activity, children will learn the treasure of knowledge contained in science knowledge, enjoy it and grow up happily.
Alpha science toys have also prepared many interesting chemistry experiment kits for children, using various magical chemical reactions to create a perfect chemical magic world for children, exploring various magical phenomena with children, and growing up to be the most powerful children's chemistry wizard.