Question

In a student experiment, a constant-volume gas thermometer is calibrated in liquid nitrogen (−196°C) and in boiling allyl alcohol (97°C). The separate pressures are 0.347 atm and 1.721 atm. Hint: Use the linear relationship

P = A + BT, where A and B are constants.

(a) What value of absolute zero does the calibration yield?

(b) What pressure would be found at the freezing point of water?

(c) What pressure would be found at the boiling point of water?

Answer 1

For liquid nitrogen (−196°C) absolute temperature is 273.15 - 196 = 77.15 K

For boiling allyl alcohol (97°C) absolute temperature is 273.15 + 97 = 370.15 K

Substitute this in expression for boiling allyl alcohol.

Substitute this in expression for boiling allyl alcohol.

Hence, the expression becomes

(a) What value of absolute zero does the calibration yield?

At absolute zero, the pressure becomes 0 atm.

(b) What pressure would be found at the freezing point of water?

The freezing point of water is 0 deg C or 273.15 K.

But in our calibration, value of absolute zero is 3.15.

Hence, the tempearture at the freezing point of water is

(c) What pressure would be found at the boiling point of water?

The boiling point of water is 100 deg C or 373.15 K.

But in our calibration, value of absolute zero is 3.15.

Hence, the tempearture at the boiling point of water is