Really cool science projects.If you’re looking for some really cool science projects, then you need to explore dry ice. If offers endless possibilities, especially for middle school science fair projects. 
What is dry ice? Dry ice is solid Carbon Dioxide. At room temperature, Carbon Dioxide is a clear odorless gas. It is found in the air.
When frozen water warms, it turns into liquid water. Water ice is “wet,” because it melts. As dry ice warms, it goes straight from being a solid (dry ice) to a gas (carbon dioxide). Dry ice doesn’t melt, so it isn’t wet. A lot of people say, “Instead of melting, dry ice evaporates.” This is almost true, but.... Technically, “evaporation” is when a liquid turns into a gas. When a solid turns into a gas, it is called sublimation. Dry ice doesn’t evaporate, it sublimates.
Under very low air pressure, water ice doesn’t melt, it sublimates, just like dry ice. On Mars, the air pressure is very low. So, there’s no liquid water on the surface of Mars. A snowball is lots of little ice crystals held together by liquid water. No liquid water means no snowballs, so on Mars, you can’t make a snowball. 
You can't make snowballs on Mars. Liquid water holds the snowflakes together in a snowball, and there is no liquid water on the surface of Mars. Cool Science Article (for advanced scientists) about snowballs on Mars. Important -- Read this page about dry ice safety.
|
