When the pressure that a gas exerts on a sealed container changes
from atm to 1.80 atm, the
temperature changes from 86.0°C to
30.0°C.

The pressure changes from 2.13 atm to 1.80 atm.

Explanation:

Given data:

Initial pressure = ?

Final pressure = 1.80 atm

Initial temperature = 86.0°C (86.0 + 273 = 359 K)

Final temperature = 30.0°C (30+273 =303 K)

Solution:

According to Gay-Lussac Law,

The pressure of given amount of a gas is directly proportional to its temperature at constant volume and number of moles.

Mathematical relationship:

P₁/T₁ = P₂/T₂

Now we will put the values in formula:

P₁ = P₂T₁ /T₂

P₁ = 1.80 atm × 359 K / 303 K

P₁ = 646.2 atm. K /303 K

P₁ = 2.13 atm

The pressure changes from 2.13 atm to 1.80 atm.