Why is the tea kettle so loud? Sid discovers that pressure forces steam out of the tea kettle, which makes it whistle so loud he needs to cover his ears. Excited to share this news with his class, Sid discovers that Teacher Suzie also has something to share: a model volcano. But how is a tea kettle related to a volcano? Just like the way pressure forces steam out of a tea kettle, pressure forces lava out of a volcano, making it erupt! Join Sid to learn about volcanoes and how to make a model volcano erupt. Go explore, discover, and make a volcano!
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Hey, you’re a scientist, like me! Come discover with Sid the Science Kid.
“Aaah! Oooh! . . . so loud! Why does the kettle whistle like that?”
Hey scientists, do you know?
“When the steam comes out of the kettle because the water’s boiling, it makes that sound.”
“And once the water boils, you turn off the heat. See? No more noise coming from the kettle.”
“Okay, but Dad, I’d like to know why the steam comes out of the kettle so fast.”
“Well, you see, when the water starts boiling, it changes into steam.
But since the kettle is closed, the steam builds up in that tiny little space.”
“And when there’s no more room, the steam starts to come out.”
“Yep! And since the way out is so tiny, the steam is under pressure and pushes hard to escape.”
“Wow! I can’t wait to learn more from Teacher Susie!”
“Okay, scientists, this morning Sid discovered something very interesting, and he wants to tell us about it.”
“Ooh, well, when water boils in a kettle, it turns into steam, and after that it comes out under pressure.”
“Exactly, Sid. And I brought in an object and put it on the table. Do you know what it is?”
“Oooh! It’s awesome, Teacher Susie! It looks like a little mountain.”
“Close. It’s a volcano, and most volcanoes are mountains.”
“Yeah, but why is there a hole at the top of your mountain?”
“Well, that’s called a crater. Every volcano has one. It’s like the top of a chimney that goes all the way down through the volcano.”
“How far down does it go, Teacher Susie?”
“Deep into the Earth, to a place where it’s so hot everything melts, even rocks.”
“The melted rocks are called magma. The more magma there is, the greater the pressure.”
“And then what happens?”
“Does the magma try to come out somehow? Like the steam in the kettle this morning?”
“That’s right, Sid! When the volcano erupts, burning magma rises in the chimney and escapes through the crater.”
“It must be really hot inside a volcano.”
“Argh! I can’t do it.”
“When magma comes out of the volcano, it is then called lava.
As lava runs down the slope of the volcano, it cools off upon contact with air and slowly turns into rock.”
“Teacher Susie, are there very many volcanoes here on Earth?”
“Yes, Gabriela. Everywhere in the world. On land and also in the oceans.”
“Teacher Susie, when you say there are volcanoes in the oceans, do you mean they’re underwater?”
“Yes, May, some volcanoes are completely underwater.
And as the lava comes out and turns to rock, they get taller and taller.
Some of them rise above sea level to form islands.”
“Teacher Susie, our volcano isn’t working. Arggh!”
“You’re right, Gerald. We say the volcano is dormant, or sleeping.”
“Teacher Susie, if it’s sleeping, does that mean it’ll wake up?”
“Right! Now let’s make a model of an erupting volcano!”
Hey! You can ask your parents to help you make one too!
First, take an empty plastic bottle. Imagine the mouth of the bottle is the crater.
Pack clay around it so that it’s hidden inside a mountain of clay.
Our volcano is ready, so to wake it up, pour vinegar into the bottle, adding a little tomato soup for coloring.
And at the end, pour a big spoonful of baking soda into the crater. Your parents can find all of these items at the grocery store.
“And the volcano erupts!”
Hey, now you can make your own volcano model too!