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 liquids. The boiling point of the liquid will be

• A. ${135}^0$C
• B. ${125}^0$C
• C. ${112}^0$C
• D. ${100}^0$C

Answer 1

The correct option is C ${112}^0$C

Initial volume $V_1=47.5$ units

Temperature of ice cold water $T_1=0^{\circ }C=273K$

Final volume of $V_2=67$ units

Applying Charle's law, we have $\frac{V_1}{T_1}=\frac{V_2}{T_2}$

(where temperature $T_2$ is the boiling point)

or $T_2=\frac{V_2}{V_1}\times T_1=\frac{67\times 273}{47.5}=385K={112}^{\circ }C$