Question

A constant pressure air thermometer gave a reading of 47.5 units of volume when immersed in ice cold water, and 67 units in a boiling liquid. The boiling point of the liquid will be

• A. $135{}^{\circ }C$
• B. $125{}^{\circ }C$
• C. $112{}^{\circ }C$
• D. $100{}^{\circ }C$

Answer 1

Answer: (C)

Initial volume $V_1=47.5unit$ Temperature of ice cold water $T_1=0^{o}C=273K$ Final volume of $V_2=67unit$ Applying Charles law, we have $\frac{V_1}{T_1}=\frac{V_2}{T_2}$ (where temperature $T_2$ is the boiling point) or $T_2=\frac{V_2}{V_1}\times T_1=\frac{67\times 273}{47.5}$ $=385K={112}^{o}C$