Answer: The boiling point of water at 81 kPa will be 298.17 K.
Explanation:
The boiling point of water is 373 K at atmospheric pressure. So, to calculate the boiling point at 81 kPa, we use the law given by Gay-Lussac.
Gay-Lussac Law states that pressure is directly proportional to the temperature when volume and moles remain constant.
Mathematically,
where,
= Initial pressure and temperature
= Final pressure and temperature
We are given:
Putting values in above equation, we get:
Hence, the boiling point of water at 81 kPa will be 298.17 K.