Calculate Entropy change of system,surrounding,and Universe

Which one of the equations below represents a reaction that is feasible at all temperatures?

• P(s) → Q(s) + R(g) endothermic

• 2L(g) + M(g) → 2N(g) exothermic

• S(g) → 2T(g) exothermic

• A(g) + B(g) → C(g) endothermic

Tags

NGSS.HS-PS1-4

NGSS.HS-PS1-5

Using the information below, answer this question.

Fe₂O₃(s) + 3H₂(g) → 2Fe(s) + 3H₂O(g)

ΔH= +96 kJ mol⁻¹, ΔS = +138 J K⁻¹ mol⁻¹

The standard entropy value for steam is

• +332 J K⁻¹ mol⁻¹

• +189 J K⁻¹ mol⁻¹

• +143 J K⁻¹ mol⁻¹

• +85 J K⁻¹ mol⁻¹

This question relates to the equilibrium gas-phase synthesis of sulphur trioxide:

2SO₂(g) + O₂(g) ⇌ 2SO₃(g)

Thermodynamic data for the components of this equilibrium are given in the table.

The standard entropy change for this reaction is

• −222 J K⁻¹ mol⁻¹

• −195 J K⁻¹ mol⁻¹

• −186 J K⁻¹ mol⁻¹

• +198 J K⁻¹ mol⁻¹

The following information concerns the equilibrium gas-phase synthesis of methanol.

CO(g) + 2H₂(g) ⇌ CH₃OH(g)

Thermodynamic data are given.

The standard entropy change for this reaction is

• −220 J K⁻¹ mol⁻¹

• +220 J K⁻¹ mol⁻¹

• −89 J K⁻¹ mol⁻¹

• +89 J K⁻¹ mol⁻¹

Calculate the entropy change of universe for the given process at -10.55 $\degree$  C

• +0.9 J/K.mol

• -0.9 J/K.mol

• +22.9 J/K.mol

• 0 J/K.mol

At high temperatures, calcium carbonate can thermally decompose to form calcium oxide and carbon dioxide:
At normal temperatures on Earth, this process does not occur; this, once again, is related to the Second Law of Thermodynamics. Prove that this reaction is non spontaneous by calculating delta S universe at 25 $\degree$   C

•  $\Delta$  S universe =+200J/K.mol

•  $\Delta$  S universe =-235.2 J/K.mol

•  $\Delta$  S universe =-400 J/K.mol

•  $\Delta$  S universe =+22 J/K.mol