When the pressure that a gas exerts on a sealed container changes from 53.0 Bar to 35.2 Bar, the temperature changes from _ C to 12.0 C. Use P1/T1=P2/T2

Explanation:

We can solve the problem by using Gay-Lussac's law, which states that:

"For a fixed mass of ideal gas kept at constant volume, the pressure of the gas is directly proportional to its absolute temperature"

Mathematically:

where

p is the pressure

T is the absolute temperature

The equation can be also rewritten as

where, in this problem:

is the initial pressure

is the final pressure

is the final temperature

Solving for T1, we find the initial temperature:

Converted into Celsius degrees,

the blue glow lasts for about 30 seconds per application. detecting the glow requires a fairly dark room.