ExamBro
ExamBro
JEE Mains · Chemistry · STD 11 - 5. Thermodynamics and thermochemistry

A fish swimming in water body when taken out from the water body is covered with a film of water of weight \(36\, g\). When it is subjected to cooking at \(100^{\circ} C\), then the internal energy for vaporization in \(kJ mol ^{-1}\) is \(......\) [nearest integer] [Assume steam to be an ideal gas. Given \(A _{ vap } H ^{\ominus}\) for water at \(373 \,K\) and \(1\, bar\) is \(41.1 \,kJ\, mol ^{-1} ; R =\) 8.31 \(J\,K ^{-1} \,mol ^{-1}\) ]

  1. A \(66\)
  2. B \(96\)
  3. C \(50\)
  4. D \(38\)
Verified Solution

Answer & Solution

Correct Answer

(D) \(38\)

Step-by-step Solution

Detailed explanation

\(H _{2} O (l) \rightarrow H _{2} O\, ( g )\) \(n =\frac{36}{18}=2\, mol\) \(\Delta U =\Delta H -\Delta n _{ g } RT\) \(=41.1-\frac{1 \times 8.31 \times 373}{1000} \,kJ / mol\) \(=38\, kJ / mol\)