Question
Consider the following statements: Assertion (A):
Alcohol, instead of mercury, is used in thermometers to measure temperatures up to 60°C. Reason (R): The freezing point temperature of alcohol is lower than mercury.Solution
Mercury freezes at -39°C, whereas alcohol freezes at temperatures well below -100°C. This makes alcohol suitable for measuring very low temperatures. On the other hand, mercury boils at 357°C, while alcohol boils at 78°C, making mercury more appropriate for measuring high temperatures. Thus, both (A) and (R) are true and (R) correctly explains (A). Hence, the correct answer is (B).