Final answer:
The internal pressure of a CO₂ fire extinguisher that was initially at 20.0 atm at 21°C increases to approximately 23.3 atm when the temperature inside a car reaches 71.1°C.
Step-by-step explanation:
The question revolves around the calculation of the internal pressure of a CO₂ fire extinguisher that has experienced a significant temperature increase. Using the ideal gas law, which states that the pressure of a gas times its volume is proportional to the number of moles times the universal gas constant times the temperature (PV = nRT), we can calculate the final pressure.
Assuming the volume and the number of moles of CO₂ remain constant, the relationship between the initial and final states can be described as P1/T1 = P2/T2. Given the initial conditions of 20.0 atm at 21°C (294.15 K), and the final condition of the fire extinguisher reaching a temperature of 71.1°C (344.25 K), the final pressure (P2) can be calculated using the values for P1 and T1. The internal pressure P2 is found to be approximately 23.3 atm after the fire extinguisher is exposed to the increased temperature.