You may have received gift cards or cash for the holiday. Remember that you can buy my lab book "Chemistry on a Budget" for $20.56 at amazon.com or $23 at lulu.com. It will take a few weeks to get to you, so order now!
This book contains 13 labs using consumable materials purchased from local stores. There are two versions of each lab, one with a ten-question conclusion and one with directions for a full lab report. This way the teacher has the option! Each lab is two pages to allow for one two-sided handout.
My previous blog post was about how deep sea fish are affected by being brought to the surface and a much lower atmospheric pressure. This is another real life example of Boyle's Law, the inverse relationship of pressure and volume of a gas.
This week I'm examining Charles' Law, that direct relationship between the temperature and volume of a gas. Comprehension is aided by focusing on Kinetic Molecular Theory
I have previously discussed Charles’ Law, and recommended a lab to complete in class, on 01/29/2014.
An experiment students could perform at home uses an empty plastic bottle with its cap – 2L, 1 L, or smaller are fine, although 2L and 1L plastic bottles may compress more easily. Students might be able to raid the family recycling bin to get empty bottles.
The bottle contains a sample of gas at room temperature. Currently there are very cold temperatures around much of the United States. Put bottle outside for 2-3 minutes and see how the gas has contracted. Another cold environment would be a freezer (if there's room).
When the bottle is back in the room temperature, it will expand as it warms up.
You might want to try this demonstration in your classroom if access to the outdoors or a freezer is easy. Maybe you can open a window in your classroom -- maybe store a plastic bottle outside for your class-- or even put it outside during class to show how quickly the change occurs.
In schools with air conditioning, you may not be able to open the window, so an empty plastic bottle must be placed outside. You will have to determine if you can complete this in the classroom.
This could be an experiment that students complete at home (perhaps for extra credit), maybe they could trace the outline of the bottle before and after cooling. Many students have phones and might be able to take pictures as well.
Just a reminder, do NOT do this with a full bottle of soda.
Check out the Topic List to help you to find past Blog entries. I hope it helps!
Have a good weekend!