The crude oil on the earth is depleting day by day, and oil prices are soaring. People want to explore a new energy source.
"Huh? Why is there another one selling salt water-powered toy cars there?" I hurried over and thought: This kind of toy is really strange. How is salt water converted into electrical energy? I picked up the box of the toy car and looked around. It said, "No batteries are needed, just two drops of salt water can start it." It's really amazing. Why not buy one and try it at home?
I ran home happily and started assembling the salt water truck. I followed the assembly instructions and assembled the two pairs of wheels, one large and one small, and installed them on the main body. Then install the motor connector, align the upper gear with the front wheel gear, and close the protective cover. Then take out a bottom base part, put a cathode plate, a non-woven fabric and an anode metal sheet on it in order to form a "FC" module and insert it into the car. Haha, the car is small, but it has about 5×3×1, and I only used it for a few minutes.
After putting together the toy car, I happily stirred the salt water and dripped it into the salt water-powered car. I put the toy car on the table, sat aside, held my breath, and stared at the toy car intently. I waited next to the toy car for more than half an hour, and I felt a little sleepy, but the car still didn't move at all. I was very confident at first, but now I feel discouraged, a little annoyed, and want to smash the car to pieces. But a voice kept reminding me: Don’t give up, try again, you will definitely succeed! I suppressed my anger and disassembled all the parts of the saltwater-powered car, checking every error carefully, even more carefully than checking the papers in the final exam. This time the truth came out and it was my own fault. My motor gear is "incompatible" with the gear groove of the front wheel. The current is already small, so why does it rotate? Not willing to give in, I dismantled all the power cars and carefully inspected them one by one, even more carefully than checking the papers in the final exam. After inspection, this time the truth came out. My motor gear does not line up with the gear groove of the front wheel, so the motor cannot drive the wheel. It's really "a mouse dropping that ruined my whole pot of porridge". I muttered as I finished assembling the power car and dripped in the salt water again. The car immediately started running, speeding around the house, and I smiled proudly.
But what is going on? Why can salt water generate electricity? I checked the information and found out: The main component of salt water is sodium chloride electrolyte, which contains a large amount of sodium ions and chloride ions. Under normal circumstances, these two ions should be able to move freely in salt water. But the nonwoven fabric installed in the car is equivalent to a filtering device, making it easier for one of the ions to pass through this "filter" and run to the other side. In this way, on both sides of the non-woven fabric, there is a positive and negative plate respectively, resulting in an imbalance of positive and negative ions and a potential difference, which replaces the battery. Then the motor rotates to drive the wheel to run.
It turned out to be like this. After reading the information, my eyes were opened immediately. Today, I understood a scientific principle through a small toy. Science is really amazing!