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° C, then the internal energy for vaporization in kJ mol -1 is [nearest integer] [Assume steam to be an ideal gas. Given A text vap H ominus for water at 373 K and 1 bar is 41.1 kJ mol -1 ; R =8.31 JK -1 mol -1 ]

Question

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° C, then the internal energy for vaporization in kJ mol -1 is [nearest integer] [Assume steam to be an ideal gas. Given A text vap H ominus for water at 373 K and 1 bar is 41.1 kJ mol -1 ; R =8.31 JK -1 mol -1 ] (A)  (B)  (C)  (D)

Tardigrade Admin · Accepted Answer

H 2 O (l) arrow H 2 O ( g ) n =(36/18)=2 mol Δ U =Δ H -Δ n g RT =41.1-(1 × 8.31 × 373/1000) kJ / mol =38 kJ / mol

H2​O(l)→H2​O(g) n=1836​=2mol ΔU=ΔH−Δng​RT =41.1−10001×8.31×373​kJ/mol =38kJ/mol

$H_{2} O (l) \to H_{2} O (g)$
$n = \frac{36}{18} = 2 m o l$
$Δ U = Δ H - Δ n_{g} RT$
$= 41.1 - \frac{1 \times 8.31 \times 373}{1000} k J / m o l$
$= 38 k J / m o l$