Science Buddies: "Ask an Expert"

identify how the volume and temperature is read on the charles apparatus

You need to be more specific in what it is you want from this forum.

Your question looks like the equivalent of "how do I read a thermometer" or "how do I determine the time on a non-digital watch".

If you want to know how to use a specific scientific tool, searching for it in google or finding the manufacture's instructions or web page is generally a good place to start.

Hi marsha,

Are you attempting to perform the Charles' Law science fair project described at https://www.sciencebuddies.org/mentorin ... p018.shtml?

If so, this sounds like a very interesting project! Please read over all of the information provided and let us know what specific questions you may have.

The basis for this experiment is that there is a relationship between the volume of a fixed amount of gas and its temperature. In this particular experiment, if you measure the volume of the air in the syringe at a range of different temperatures, you will see that it changes! This raises (at least!) a couple of questions:

1. Why does the volume of the gas change with temperature?

2. After you have performed the experiment, if you have a particular volume of air in your syringe, can you determine the temperature (without a thermometer)?

After you have performed your experiment (at least three separate times, per the instructions), you will plot your results on a graph in the form of air volume vs. temperature. Within this temperature range, you should now have the tools to be able to predict the temperature based on the volume of air in the syringe - and all without the aid of a thermometer! How cool is that?!

Now, your experiment does not use the actual Charles' apparatus, but a simple equivalent. Based on your background reading, can you see how a manometer can be used to measure the pressure in a given closed system? (This is an extremely useful instrument when working on reduced-pressure systems.)

I hope this helps, and please be sure to post back to the forum with any questions you may have.

Good luck!
Geoff.