A gas occupies a volume of `250 cm^(3)` at `745` torr and `25^(@)C` . What additional pressure is required to reduce the volume of the gas to `200 cm^(2)` at the same temperature ?

Answer

`186.25` torr

Explanation

`P_(1)= 745` torr , `P_(2) = ?`
`V_(1) = 250 cm^(3) , V_(2) = 200 cm^(3)`
Since temperature is constant, Boyles' Law is applicable.
`P_(1)V_(1) = P_(2)V_(2)` or `P_(2) (P_(1)V_(1))/(2) = ((745 "torr") xx (250 cm^(3)))/((200 cm^(3))) = 931.25 "torr"`.
Additional pressure to be applied `= (931.25 - 745) = 186.25` torr