Solveeit Logo

Question

Chemistry Question on Thermodynamics

Formation of ammonia is shown by the reaction, N2(g)+3H2(g)2NH3(g)N_{2\left(g\right)}+3H_{2\left(g\right)} \to 2NH_{3\left(g\right)}; ΔrH=91.8kJmol1\Delta_{r}H^{\circ} = -91.8\,kJ\,mol^{-1} What will be the enthalpy of reaction for the decomposition of NH3NH_3 according to the reaction? 2NH3(g)N2(g)+3H2(g);ΔrH=?2NH_{3\left(g\right)}\to N_{2\left(g\right)} + 3H_{2\left(g\right)}; \Delta_{r}H^{\circ} = ?

A

91.8kjmol1-91.8 \,kj \,mol^{-1}

B

+91.8kjmol1+ 91.8\,kj \,mol^{-1}

C

45.9kjmol1-45.9\,kj \,mol^{-1}

D

+45.9kjmol1+ 45.9\,kj \,mol^{-1}

Answer

+91.8kjmol1+ 91.8\,kj \,mol^{-1}

Explanation

Solution

The sign of ΔH\Delta H is reversed.