At constant pressure and temperature, which of the following statements is true for the reaction: N₂O₅(s)$\rightarrow$ 2NO₂(g)+ ½O₂(g), $\Delta$H_r = 109.5 kJ.mol^-¹ at 298 K. A)$\Delta$H is independent of the physical states of the reactants. B) $\Delta$H = $\Delta$U C) w = 0 D) $\Delta$H $\Delta$U

Question

At constant pressure and temperature, which of the following statements is true for the reaction: N₂O₅(s)$\rightarrow$ 2NO₂(g)+ ½O₂(g), $\Delta$H_r = 109.5 kJ.mol^-¹ at 298 K. A)$\Delta$H is independent of the physical states of the reactants. B) $\Delta$H = $\Delta$U C) w = 0 D) $\Delta$H <$\Delta$U E) $\Delta$H > $\Delta$U

Quizplus · Accepted Answer

At constant pressure, when a reaction involves gases, the change in enthalpy ($\Delta$H) is greater than the change in internal energy ($\Delta$U) due to the work done by the system to expand against atmospheric pressure. This is described by the equation $\Delta$H = $\Delta$U + P$\Delta$V, where P$\Delta$V represents the work done for volume expansion. Since the reaction produces gases, there is a positive volume change, making $\Delta$H greater than $\Delta$U.

At Constant Pressure and Temperature, Which of the Following Statements →\rightarrow→

At Constant Pressure and Temperature, Which of the Following Statements $\rightarrow$