Chemistry help

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