Enthalpies of formation of CCl 4( g ), H 2 O ( g ), CO 2( g ) and HCl ( g ) are -105,-242,-394 and -92 kJ mol -1 respectively. The magnitude of enthalpy of the reaction given below is kJ mol -1 . (nearest integer) CCl 4( g )+2 H 2 O ( g ) arrow CO 2( g )+4 HCl ( g )

Question

Enthalpies of formation of CCl 4( g ), H 2 O ( g ), CO 2( g ) and HCl ( g ) are -105,-242,-394 and -92 kJ mol -1 respectively. The magnitude of enthalpy of the reaction given below is kJ mol -1 . (nearest integer) CCl 4( g )+2 H 2 O ( g ) arrow CO 2( g )+4 HCl ( g ) (A)  (B)  (C)  (D)

Tardigrade Admin · Accepted Answer

Δ r H =∑ H p -∑ H R =(-394+4 ×-92)-(-105+(2 ×-242)) =-173 kJ / mol

Q. Enthalpies of formation of CCl4​(g),H2​O(g),CO2​(g) and HCl(g) are −105,−242,−394 and −92kJ mol −1 respectively. The magnitude of enthalpy of the reaction given below is ___kJmol−1 . (nearest integer) CCl4​(g)+2H2​O(g)→CO2​(g)+4HCl(g)

Δr​H=∑Hp​−∑HR​ =(−394+4×−92)−(−105+(2×−242)) =−173kJ/mol

$Δ_{r} H = \sum H_{p} - \sum H_{R}$
$= (- 394 + 4 \times - 92) - (- 105 + (2 \times - 242))$
$= - 173 k J / m o l$