Question

At which temperature will water boil when the external pressure is 17.5 torr

Answer 1

Answer: The temperature required to boil will be 8.6 K

Explanation: The normal boiling point of water is taken as 100 °C

The pressure conditions at this temperature is 1 atm

Now, to calculate the temperature required to boil water present at 17.5 torr, we use Gay-Lussac's Law, which states that the pressure is directly proportional to the temperature at constant volume and number of moles.

Mathematically,

`(P_1)/(T_1)=(P_2)/(T_2)`

Initial conditions:

`P_1=1atm=760torr`

`T_1=100^oC=(100+273)K=373K`

Final conditions:

`P_2=17.5torr`

`T_2=?K`

Putting in above equation, we get

`(760)/(373)=(17.5)/(T_2)`

`T_2=8.6K`