Question

The volume of a gas-filled balloon is 20.0 L at 250 K and 145 kPa pressure. What would the volume be at standard temperature and pressure (STP)?

Answer 1

Answer : The volume of gas will be, 31.26 L

Solution :

At STP, pressure of gas is 101.3 kPa and temperature of gas is 273 K.

The combined gas equation is,

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

where,

`P_1` = initial pressure of gas = 145 kPa

`P_2` = final pressure of gas = 101.3 kPa

`V_1` = initial volume of gas = 20 L

`V_2` = final volume of gas = ?

`T_1` = initial temperature of gas = 250 K

`T_2` = final temperature of gas = 273 K

Now put all the given values in the above equation, we get the final volume of gas.

`(145kPa* 20L)/(250K)=(101.3kPa* V_2)/(273K)`

`V_2=31.26L`

Therefore, the volume of gas will be, 31.26 L