Use the mouse. Choose which variable you will test by clicking nest to them in the bottom right corner. Then, you can move around the red bars at the top using the mouse. The gray bar will react to what you do.
I didn't make the box size change because it would be too difficult to control the particles. To get a lot of gas, choose moles as your variable, then put the temperature way down. I made this to study for Chemistry! It is a demonstration of the relationship between pressure, volume, amount (moles), and temperature of a gas. [Amcerbu]Moles are units that measure "quantity" of substance. One mole = 6.022 * 10 ^ 23 units. If you're talking about moles of water, units are the number of molecules, or, for an element like carbon (graphite) the number of atoms. Moles are useful in dealing with reactions. It's the number of molecules that counts, not the mass. If you were reacting Na and H2O (don't do this at home), you would need equal moles of each, not equal masses, for everything to react. [/] The formula is PV=nRT, meaning pressure x volume = moles x 0.0821 x temperature. Pressure is measured in atmospheres (atm). Volume is in liters (L). Temperature is in kelvins (K). Kelvin is equal to degrees celsius + 273. Have fun, if you have question look on Google or ask me. Check google first though.