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Rapid Change: Boiling — Reading Comprehension

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This engaging Grade 4-5 science passage explores 'Rapid Change: Boiling', aligning with NGSS standards for understanding matter and its interactions. Students will learn how boiling is a rapid change from liquid to gas, the role of temperature, and real-life applications such as cooking and the water cycle. The passage introduces and defines key vocabulary like evaporation, condensation, and boiling point, with clear examples and simple explanations suitable for upper elementary students. An Interesting Fact section adds curiosity, while a detailed glossary supports vocabulary development. The resource includes a multiple-choice quiz and writing activities that foster scientific thinking, comprehension, and connections to everyday life. All content is audio integrated, making it accessible for diverse learners. This resource is perfect for classroom use, homework, or science centers, and provides a comprehensive, standards-aligned exploration of how boiling affects matter and our daily experiences.

CONTENT PREVIEW

cooking, pot, risotto, kitchen, food, nature, cook, nutrition, eat, stove, rice, steam, boil, closeup, close-up, casserole, mist, heat, boiling, water, hot, droplets — The boiling point is the exact temperature where the liquid starts to change quickly into a gas. Image by scratsmacker / Pixabay.

Boiling is when a liquid changes into a gas throughout the entire liquid. This happens when you add enough heat energy to the liquid. Understanding boiling helps us cook food, purify water, and explain how matter changes from one state to another.

When you heat water in a pot on the stove, something interesting happens. As the water gets hotter, bubbles begin to form at the bottom of the pot. These bubbles are not air—they are pockets of water that have turned into a gas called water vapor. The bubbles rise through the liquid and burst at the surface, releasing the water vapor into the air. This process happens throughout the entire pot of water, not just at the top.

Boiling happens at a specific temperature called the boiling point. For water, this temperature is 212 degrees Fahrenheit (100 degrees Celsius) at sea level. When water reaches this temperature, it boils vigorously with many bubbles forming rapidly. The heat energy from the stove gives water molecules enough energy to break free from the liquid and become a gas.

Boiling is different from evaporation, which is another way liquids turn into gas. Evaporation only happens at the surface of a liquid and can occur at any temperature. For example, a puddle of water on the sidewalk slowly evaporates on a warm day, even though the water never gets hot enough to boil. The water molecules at the surface gain enough energy from the sun to escape into the air as water vapor. However, during boiling, the change from liquid to gas happens throughout the entire liquid, not just at the surface.

Think of evaporation like students leaving a classroom one at a time through the door (the surface). Boiling is like opening all the doors and windows at once, with students leaving from everywhere in the room at the same time. Both processes turn liquid water into water vapor, but boiling is much faster and more energetic because it happens everywhere in the liquid at once.

Interesting Fact: Water boils at lower temperatures on top of tall mountains because the air pressure is lower there. On Mount Everest, water boils at only 160 degrees Fahrenheit instead of 212 degrees!

What is boiling?

Liquid changing to gas throughout liquidLiquid changing to solid slowlyGas changing to liquid at surfaceSolid changing to liquid with heat

What are the bubbles in boiling water?

Pockets of air from outsideWater vapor gas pocketsPieces of ice meltingDirt particles rising up

What is water's boiling point temperature?

100 degrees Fahrenheit160 degrees Fahrenheit212 degrees Fahrenheit300 degrees Fahrenheit

Why does boiling happen faster than evaporation?

It only happens at surfaceIt happens throughout entire liquidIt needs less heat energyIt only happens on mountains

Where does evaporation occur in liquid?

Throughout the entire liquidOnly at the bottomOnly at the surfaceOnly in the middle

What gives water molecules energy to boil?

Cold air from outsideHeat energy from stovePressure from the potLight from the sun