I think 1 is right.
I don't know about 2.
For 3 you want to know delta G for the reaction. You can calculate that from dG = dH - TdS. You have dH but you don't have T nor dS so I don't think you can calculate dG with two unknowns.
4. The answer isn't c. The mistake you made is adding dH to TdS without changing units first. Notice that dH is in kJ and TdS is in J. You must change one of them before adding; when you do that you won't get c.
5. dGo rxn = (n*dGo formation products) - (n*dGo formation reactants).
Then dG = -RT*ln*K and calculate for K.
Please help me with these problems, the book examples very different. I'm really confused. Any help with these will help me immensely. Thank you in advance! What I got were: 1.)c 2.)d 3.)a 4.)c 5.)b
1.) When is any endothermic reaction spontaneous?
a.)When ΔSreaction > 0
b.)When ΔSsurroundings > 0
c.)When ΔSuniverse > 0
d.)None of the above
2.) How many total microstates are possible for 2 particles that are trapped in 2 connecting flasks?
a.)1 microstate
b.)2 microstates
c.)3 microstates
d.)4 microstates
e.)5 microstates
f.)6 microstates
3.) Determine the spontaneity of this reaction:
4 NH3(g) + 3 O2(g) → 2 N2(g) + 6 H2O(g) ΔHrxn = -1267
a.)The reaction is spontaneous at high temperatures
b.)The reaction is spontaneous at low temperatures
c.)The reaction is NOT spontaneous at any temperature.
d.)The reaction is spontaneous at all temperatures
e.)It is impossible to determine the reaction
4.) Estimate ΔG°rxn for the following reaction at 387 K.
HCN(g) + 2 H2(g) → CH3NH2(g) (ΔH°= -158.0 kJ; ΔS°= -219.9 J/K)
a.)+243 kJ
b.)-72.9 kJ
c.)+84.9 kJ
d.)-92.5 kJ
e.)-188 kJ
5.) Use the free energies of formation given below to calculate the equilibrium constant (K) for the following reaction at 298 K. [2 HNO3(aq) + NO(g) → 3 NO2(g) + H2O(l)]
(ΔG°f (kJ/mol): -110.9; 87.6; 51.3; -237.1)
a.)8.71 × 10^8
b.)0.980
c.)1.15 × 10^-9
d.)1.02
e.)5.11 × 10^-4
1 answer
1 answer