Chemistry Help?

1. place them in order of increasing stability:

NO (g) SO3 (g) NaCO3 (s) H2O (l)

2. Calculate the heat of reaction for N2 (g) + O2 (g)  2NO (g), given the following:

   4NH3 (g) + 5O2 (g)  4NO(g) + 6H2O(l)        Hrxn = −1170 kJ

   4NH3 (g) + 3O2 (g)  2N2 (g) + 6H2O (l)       Hrxn = −1530 kJ

3. Calculate the enthalpy of reaction for phosphorous trichloride reacting with chlorine gas

to produce phosphorous pentachloride, given the following:

  2P (s) + 3Cl2 (g)  2PCl3 (l) Hrxn = −640 kJ

   2P (s) + 5Cl2 (g)  2PCl5 (s) Hrxn = −886 kJ