Question

Consider the endothermic reaction: N2 (g) 2 H2 (g) → N2H4 (l) The entropy change of this reaction is ________ and the enthalpy change is ________, so at a very high temperature, this reaction is probably ________. Consider the endothermic reaction: N2 (g) 2 H2 (g) → N2H4 (l) The entropy change of this reaction is ________ and the enthalpy change is ________, so at a very high temperature, this reaction is probably ________. unfavorable; unfavorable; nonspontaneous unfavorable; favorable; spontaneous favorable; unfavorable; spontaneous favorable; unfavorable; nonspontaneous unfavorable; unfavorable; spontaneous

Answer 1

Answer: unfavourable, unfavourable, non spontaneous

Step-by-step explanation:

Endothermic reactions are those in which heat is absorbed by the system and exothermic reactions are those in which heat is released by the system.

`\Delta H` for Endothermic reaction is positive and
`\Delta H` for Exothermic reaction is negative.

Entropy is the measure of randomness or disorder of a system. If a system moves from an ordered arrangement to a disordered arrangement, the entropy is said to decrease and vice versa.

For the reaction:

`N_2(g)+2H_2(g)\rightarrow N_2H_4(l)`

`\Delta S` is negative as the randomness decreases when gases convert into liquid.

For reaction to be spontaneous,
`\Delta G=-ve` and favourable conditions are
`\Delta H=-ve` and
`\Delta S=+ve`

Using Gibbs Helmholtz equation:

`\Delta G=\Delta H-T\Delta S`

`\Delta G=(+ve)-T(-ve)`

`\Delta G=(+ve)(+ve)`

`\Delta G=+ve`

Thus the reaction is non spontaneous at all temperatures.