Question

Un gas se encuentra a una presión constante y a una temperatura de 30°C. Si la temperatura aumenta a 45°C, su presión varía a 6 atm. ¿Cuál era la presión inicial del gas? Transforma los °C en °K.

Answer 1

P1 = 5.76 atm

Step-by-step explanation:

To find the initial pressure of the gas you use the equation for ideal gases, for both temperatures and pressures:

`P_1V=nRT_1\\\\P_2V=nRT_2\\\\`

T1: initial temperature = 30°C = 303.15K

T2: final temperature = 45°C = 318.15K

P1: initial pressure = ?

P2: final pressure = 6atm

n: number of moles

R: ideal gas constant

The number of moles and R are constant, you can dive the first equation into the second and solve for P1:

`(P_1V)/(P_2V)=(nRT_1)/(nRT_2)\\\\(P_1)/(P_2)=(T_1)/(T_2)`

`P_1=(T_1P_2)/(T_2)`

Finally, you replace the values of T1, P2 and T2:

`P_1=((303.15K)(6atm))/(318.15K)=5.71atm`

hence, the initial pressure of the gas was 5.71 atm