4. The temperature of a fixed mass of gas in a rigid container is decreased from 127.00 degrees Celsius to 27.0 degrees Celsius. The initial pressure was 1.5 atm. Which is
closest to the new pressure after cooling?
A) 0.5 atm
B) 1 atm
C) 2 atm
D) 2.5 atm
Can you explain how you got the answer as well ?

B) 1 atm

Explanation:

According to Gay-Lussac's law, the pressure of a given amount of gas at constant volume is directly proportional to its temperature (in Kelvin). This is mathematically expressed as:

P₁/T₁ = P₂/T₂

From the problem, we have the following data:

P₁= 1.5 atm

T₁= 127 °C + 273 = 400 K

T₂= 27 °C + 273 = 300 K

Thus, we calculate P₂ - final pressure - as follows:

P₂ = P₁/T₁ x T₂ = (1.5 atm)/(400 K) x 300 K = 1.125 atm

Therefore, the option which is closest to the new pressure after cooling is B) 1 atm