Octene (C8H16) can be converted into octane (C8H18) following the reaction below. ΔH° for the reaction is −125.52 kJ/mol and ΔS° is −129.9 J/K·mol. C8H16(g) + H2(g) → C8H18(g) a. At what temperatures (high/low/all/none) is the reaction spontaneous? Support your answer with clear reasoning.   b. Is the reaction spontaneous at 25°C? Support your answer with words or calculations.

For each reaction, calculate ΔH°rxn, ΔS°rxn, and ΔG°rxn at 25 °C and state whether or not the reaction is spontaneous. If the reaction is not spontaneous, would a change in temperature make it spontaneous? If so, should the temperature be raised or lowered from 25 °C?a. 2 CH4( g)------->C2H6( g) + H2( g)b. 2 NH3( g)------> N2H4( g) + H2( g)c. N2( g) + O2( g)-------->2 NO( g)d. 2 KClO3(s)-------->2 KCl(s) + 3 O2( g)

Consider the reaction below for the decomposition of carbon tetrachloride gas:  CCl4(g)    ------>     C(s)     +        2Cl2 (g)    ΔH = + 95.7 kJ;  ΔS = + 142.2 J/K  If the reaction above is not spontaneous at 25 oC, determine at what temperature (if any) the reaction becomes spontaneous.

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A reaction has AH°= 100 kJ/mol and AS°= 250 J/mol.K. Is the reaction spontaneous at room temperature? If not, under what temperature conditions will it become spontaneous?

A reaction has a ΔH of -87.36 kJ and a ΔS of -175.3 J/K. At what temperature (in K) does the reaction become spontaneous?     626.4 K     This reaction is always spontaneous     498.3 K     434.6 K     This reaction is never spontaneous

For a given reaction, ΔH∘∘= +35.5 kJ/mol and ΔS∘∘= +83.6 J/(K∙∙ mol). In what temperature range is the reaction spontaneous? Assume that ΔH∘∘ and ΔS∘∘ do not vary with temperature.

From the values of ΔH and ΔS predict which of the following reactions would be spontaneous at 25°C. Calculate the minimum temperature at which each reaction will become spontaneous. Enter "None" if the reaction is not spontaneous at any temperature. ΔH = -75.8 kJ/mol,  ΔS = 126  J/K · mol

The enthalpy and entropy changes for a reaction at 298 K are ∆H = 46 kJ and ∆S = 190 J/K. Which of the following best describes this reaction A) The reaction is spontaneous and driven by favorable changes in the enthalpy and entropy. B) The reaction is not spontaneous because heat is absorbed. C) The reaction is not spontaneoius but could be spontaneous at a higher temperature. D) The reaction is spontaneous and driven by the favorable entropy change.

Which are spontaneous at all temperatures? Choose one or more: 2H,0(g) + SO,(g) - 152.4 J/K 2H,S(g) +30,(g) AH°. rxn = - 1037 kJ, AS°. rxn → 2SO3(g) - 197.8 kJ, ASº. 2SO,(g) +O2(g) AH°. rxn - 187.8 J/K rxn O so,(8) + H,0(1) → H,SO4(1) AH°. rxn - 132.5 kJ, AS° - 169.9 J/K rxn S(g) +O2(8) –→ SO,(g) - 574.0 kJ, AS°, ΔΗ. rxn - 124.6 J/K rxn none of the above