Heat and Thermodynamics

Solved Problems

Q1. A travelling microscope was used to note the positions of the mercury meniscus of a mercury-in-glass thermometer. The reading corresponding to melting ice was 1.23 mm. In steam at a pressure of 74.24 cm of mercury, the reading was 18.56 mm. What is the temperature in°C when the reading is 10.75 mm? What will be the reading corresponding to 50°C? Assume that the boiling point of water changes by 1°C for a change of pressure of 27 mm of mercury.

 

Ans: We know at a pressure of 76 cm of mercury, steam point is 100°C; as boiling point changes by 1°C for a change of pressure of 27 mm of mercury, so at a pressure of 74.24 cm of mercury, the steam point will be

 

 

We also know (steam point – melting point)

where l stands for ...