slevey,+gay-lussac's+law.

gay-lussac's law: the pressure-temperature relationship.
in 1802, joseph gay-lussac recognized that for every kelvin of temperature change, the pressure of a confined gas changes by 1/273. his law states that the pressure of a fixed mass of a gas at constant volume varies directly with the kelvin temperature.

//this is how the law is expressed:// P1/T1 = P2/T2

P1 = initial pressure. T1 = initial temperature. P2 = final pressure. T2 = final temperature.

a gas in a container is at a pressure of 3 atm at 25° celcius. directions on the container warn the user not to keep it in a place where the temperature exceeds 52° celcius. what would the gas pressure in the container be at 52° celcius.
 * here is a practice problem:**

//converting celcius to kelvin:// remember that in chemistry, we use kelvin in problems, not celcius! add 273 to every celcius temperature. 25° celcius + 273 = 298 K. 52° celcius + 273 = 325 K.

//fill in your variables:// P1 = 3 atm. T1 = 298 K. P2 = unknown. T2 = 325 K.

//rearranging the equation to find the unknown:// since P2 is our unknown, we have to isolate it from the original equation so we can solve for it. the equation turns into this: __P1T2__ = P2 T1

//fill in the correct values for the variables:// __(3 atm)(325 K)__ = P2 = 3.27 atm 298 K

as expected, a temperature increase at constant volume causes the pressure of the contents in the container to increase. nice.

[joseph gay-lussac.] back to the main page.