Problem: Which of the following reactions would you predict to be spontaneous at all temperatures (assuming ΔH°­rxn does not change significantly with temperature)?H2S(g) + 2 O2(g) → H2SO4(l) ΔH°­rxn= –793 kJ/mol2 Ag(s) + 3 N2(g) → 2 AgN3(s) ΔH°­rxn = +1240 kJ/molC6H6(l) + 3 H2(g) → C6H12(l) ΔH°­rxn = –207 kJ/molNa2CO3(s) + 2 HCl(aq) → 2 NaCl(aq) + H2O(l) + CO2(g) ΔH°­rxn = –834 kJ/molCaCO3(s) → CaO(s) + O2(g) ΔH°­rxn = +179 kJ/mol

FREE Expert Solution

We’re being asked to determine which reactions is spontaneous at all temperatures.

Recall that when ΔH and ΔS are given, we can determine the spontaneity of the reaction based on their signs

We can use the Punnett square shown below:

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Problem Details

Which of the following reactions would you predict to be spontaneous at all temperatures (assuming ΔH°­rxn does not change significantly with temperature)?

H2S(g) + 2 O2(g) → H2SO4(l) ΔH°­rxn= –793 kJ/mol

2 Ag(s) + 3 N2(g) → 2 AgN3(s) ΔH°­rxn = +1240 kJ/mol

C6H6(l) + 3 H2(g) → C6H12(l) ΔH°­rxn = –207 kJ/mol

Na2CO3(s) + 2 HCl(aq) → 2 NaCl(aq) + H2O(l) + CO2(g) ΔH°­rxn = –834 kJ/mol

CaCO3(s) → CaO(s) + O2(g) ΔH°­rxn = +179 kJ/mol