Question

A gas of 250 ml at 20°C and 720 Torrs. What volume would the gas occupy at STP ?

Answer 1

Answer: The gas would occupy volume of 221 ml at STP

Step-by-step explanation:

Combined gas law is the combination of Boyle's law, Charles's law and Gay-Lussac's law.

The combined gas equation is,

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

where,

`P_1` = initial pressure of gas = 720 torr

`P_2` = final pressure of gas = 760 torr (at STP)

`V_1` = initial volume of gas = 250 ml

`V_2` = final volume of gas = ?

`T_1` = initial temperature of gas =
`20^oC=273+20=293K`

`T_2` = final temperature of gas =
`273K` (at STP)

Now put all the given values in the above equation, we get:

`(720* 250)/(293)=(760* V_2)/(273)`

`V_2=221ml`

The gas would occupy volume of 221 ml at STP