What is Ice? - Simple Chemistry
Welcome to Quatr.us Study Guides!

What is Ice?

Glacier
Perito Moreno glacier, Argentina
(thanks to Argentina's Travel Guide)

January 2017 - When water gets colder than 32 degrees Fahrenheit or zero degrees Celsius, it freezes into ice. As the water gets colder, the molecules of water lose their energy and move more slowly - that's what it means to be colder. When the molecules move more slowly, it is easier for them to hook on to each other by sharing electrons. When enough of the molecules hook on to each other, they form a pattern that looks like a bunch of hexagons, all locked in together, and that is ice. Because the molecules are all locked into place, ice is hard and stiff.

Ice crystals
Molecular structure of ice

When water freezes into ice, it takes up about 9 per cent more room than it did when it was water. That's because when the water molecules are locked together, they are farther apart from each other than when they are bouncing around loose as a liquid. It's as if you were standing in a crowd of people, and then you were standing in a crowd of people all holding hands with their elbows straight and their arms sticking straight out from their bodies. The people would be further apart than before.

Water with salt in it, like in the oceans, can freeze too, but it won't freeze until it gets much colder than fresh water ice. That's because the salt molecules arrange themselves around the water molecules like little fences and keep the water molecules from hooking together. But if it gets cold enough, about 28.5 degrees Fahrenheit or -2 Celsius, ocean water will freeze too.

Because it's cold in space, the water in space is mostly in the form of ice. Most of the water in the universe is probably in the form of ice. On Mars, and on the moons of Jupiter, there is also a lot of ice.

On Earth, the temperature is often just right to have liquid water, which is good because water is necessary for all life on Earth. But still a lot of the water on Earth is in the form of ice. At some times in the past, like during the Proterozoic period about two billion years ago, the whole Earth was probably covered in ice. The last major glacial period, when ice covered the Earth as far south as Krakow in Poland, and almost all of Canada, ended about 10,000 years ago, but another glacial period could start again anytime - we don't really know what makes them start. The glacial periods, when there is a lot of ice, are much longer than the warmer periods like the one we are in now.

Learn by doing - Ice Science Project
Making ice cream without a freezer
More about global warming
More about water
More about steam

Bibliography and further reading:

Water
Steam
Weather
Molecules
Chemistry
Quatr.us home


Please help other teachers and students find us: link to this page from your class page.
Karen Carr is Associate Professor Emerita, Department of History, Portland State University. She holds a doctorate in Classical Art and Archaeology from the University of Michigan. Follow her on Instagram, Pinterest, or Twitter, or buy her book, Vandals to Visigoths.
Karen Carr is Associate Professor Emerita, Department of History, Portland State University. She holds a doctorate in Classical Art and Archaeology from the University of Michigan. Follow her on Instagram or Twitter, or buy her book, Vandals to Visigoths.
Sign up for more free articles and special offers in Quatr.us' weekly newsletter:
We will never share your e-mail address unless you allow us to do so. View our privacy policy. Easy unsubscribe links are provided in every email.
Check out our new ebook: Short and Simple: Ancient Greek Myths! - just out! Twenty-five easy to read, illustrated stories, from Pandora to Medea, Icarus, and the Trojan Horse (you can read these online as samples). Get it this week for just $14.99, five dollars off the regular price of $19.99.
Cite this page
  • Author: K.E. Carr
  • Title:
  • Site Name: Quatr.us Study Guides
  • Publisher: Quatr.us
  • Date Published:
Did you find what you needed? Ask your teacher to link to this page so other people can use it too! Send it in and win a Quatr.us "Great Page!" award!
Sign up for more free articles and special offers in Quatr.us' weekly newsletter:
We will never share your e-mail address unless you allow us to do so. View our privacy policy. Easy unsubscribe links are provided in every email.
Comment on This Article
Quatr.us is loading comments...
(Comments will appear after moderation, if they are kind and helpful. Feel free to ask questions, and we'll try to answer them.)
Cite this page
  • Carr, K.E. . Quatr.us Study Guides, . Web. 24 May, 2017
ADVERTISEMENT