Question

The STP volume of an ideal gas is `2.78` `m^3`. What is the pressure of the sample at `1.75` `m^3` and `27°C`?

Answer 1

`P_2=1.75 atm`

Explanation:

The initial conditions are:
STP means: `T_1=273K` and `P_1=1atm`
The volume of the gas is `V_1=2.78m^3`

Since the volume (`V_2=1.75m^3`) and temperature (`T_2=300K`) are changing at the same time, the new pressure could be found using:

`(P_1V_1)/(T_1)=(P_2V_2)/(T_2)`

`=>P_2= (P_1V_1)/(T_1)xx(T_2)/(V_2)=(1atmxx2.78cancel(m^3))/(273cancel(K))xx(300cancel(K))/(1.75cancel(m^3))=1.75 atm`