Boiling Point and Pressure – Rankers Physics

Calorimetry: Practice Problem & Solution

Assertion (A): Water can be made to boil without heating. Reason (R): Boiling point of water is lowered by decreasing pressure.  
Both (A) & (R) are true and the (R) is the correct explanation of the (A)
Both (A) & (R) are true but the (R) is not the correct explanation of the (A)
(A) is true but (R) is false
Both (A) and (R) are false

Solution Explained:

To solve this problem, we apply the core principles of Calorimetry. Understanding the underlying formula is key to arriving at the correct answer below:

Boiling occurs when vapor pressure equals external pressure. Reducing external pressure lowers the boiling point of water. Thus, water can be made to boil at room temperature or even lower without external heating. Both (A) and (R) are true, and (R) correctly explains (A).

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