Question

The instruction booklet for your pressure cooker indicates that its highest setting is 13.5 psi . You know that standard atmospheric pressure is 14.7 psi, so the booklet must mean 13.5 psi above atmospheric pressure. At what temperature in degrees Celsius will your food cook in this pressure cooker set on "high"?

Answer 1

Answer: The temperature in the pressure cooker set on high is 250.71°C

Explanation:

STP conditions:

Pressure = 14.7 psi

Temperature = 273 K

To calculate the final temperature of the system, we use the equation given by Gay-Lussac Law. This law states that pressure of the gas is directly proportional to the temperature of the gas at constant pressure.

Mathematically,

$\frac{P_1}{T_1}=\frac{P_2}{T_2}$

where,

$P_1\text{ and }T_1$ are the initial pressure and temperature of the gas.

$P_2\text{ and }T_2$ are the final pressure and temperature of the gas.

We are given:

$P_1=14.7psi\\T_1=273K\\P_2=(14.7+13.5)psi=28.2psi\\T_2=?$

Putting values in above equation, we get:

$\frac{14.7psi}{273K}=\frac{28.2psi}{T_2}\\\\T_2=\frac{28.2\times 273}{14.7}=523.71K$

Converting the temperature from kelvins to degree Celsius, by using the conversion factor:

$T(K)=T(^oC)+273$

$523.71=T(^oC)+273\\T(^oC)=(523.71-273)K=250.71^oC$

Hence, the temperature in the pressure cooker set on high is 250.71°C