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Have you ever wondered why a tiny, hard corn kernel suddenly turns into fluffy popcorn when you heat it? It’s all because of water trapped inside the kernel!

Each popcorn kernel has a little bit of water sealed inside it. When you heat the kernel, the water gets hotter and turns into steam. But the hard outer shell keeps the steam trapped inside.

As the temperature rises, the steam pushes harder and harder against the shell. Finally, the pressure becomes too much and POP! 💥 The shell bursts open.

At the same time, the hot, soft starch inside the kernel expands quickly. It cools and becomes the white, fluffy popcorn we love to eat.

So, the next time you hear POP! POP! POP!, remember: you are watching heat, water, pressure, and starch working together! 🔬🍿

Science word: Pressure — a pushing force acting on something.

Think like a scientist: Why do you think popcorn kernels don't pop when they are completely dry?

The sky is blue because gases in Earth's atmosphere scatter short blue light waves from the Sun in all directions more than other color waves.