Hello and welcome back to the Curious Kid podcast. Today, we are going to learn about an invention that is so important in our everyday lives, but has only existed for about 100 years. It's amazing to think of how different things must have been before this invention was

widely used. This week we are getting curious about refrigerators. I can't even imagine how much

different life would be without refrigerators. Today, we are going to learn exactly how people

kept their food cold before refrigerators, how refrigerators

work, and so much more. What's the question of the week? The question of the week is,

what percentage of homes in the United States have two or more refrigerators? While you're

thinking about the answer, let's start learning.

Refrigerators help keep your food from getting spoiled.

And they do that by lowering the reproduction rate of bacteria.

Let's take milk, for example.

Milk can usually stay fresh in a refrigerator for a week or two after you

purchase it. But it would probably go bad if you kept it out of the refrigerator for just a few hours.

And that's because putting it in the refrigerator prevents bacteria from spoiling the milk. It's the

bacteria that spoils food and drinks when they go

bed. Refrigerators are kept a few degrees above the freezing point of water. This is really important.

Are you familiar with the three phases of matter? The three different phases are solid, liquid, and gas.

So let's take water, for example.

Water is a liquid.

When it freezes, which happens at a temperature of 32 degrees Fahrenheit,

or zero degrees Celsius, it turns into ice, which is a solid. You can also turn water into

a gas by heating it up. The boiling point of water is 212 degrees Fahrenheit or 100 degrees Celsius.

At that temperature, the water turns into a gas called water vapor.

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