If the initial temperature of an ideal gas at 2.250 atm is 62.0 degrees C, what final temperature would cause the pressure to be reduced to 1.750 atm?

1 Answer
Oct 22, 2017

The final temperature would be 260.7 K or 12.45C.

Explanation:

This question is an example of Gay-Lussac's law relating temperature and pressure. This law states that the pressure of a given amount of gas held at constant volume is directly proportional to the Kelvin temperature. This means that if the pressure increases, the temperature also increases, and vice versa. The equation for this law is:

P1T1=P2T2

The temperature must be in Kelvins. To convert degrees Celsius to Kelvins, add 273.15 to the Celsius temperature.

Organize the data:

Known

P1=2.250 atm

T1=62.0C+273.15=335.2 K

P2=1.750 atm

Unknown

T2

Solution

Rearrange the equation to isolate T2. Insert the known data and solve.

T2=P2T1P1

T2=1.750atm×335.2K2.250atm=260.7 K

To convert Kelvins to degrees Celsius, subtract 273.15 from the Kelvin temperature.

260.7273.15=-12.45C