Chemistry questions...please help!! any advice would be great!!?

1.For the reaction whose reactants and products are:





reactants: NH3 (g) O2 (g)





products: NO2 (g) H2O (g)





calculate the standard entropy change (J/mol-K).








2.Calculate 螖Suniv in J/mol-K for the above process at 298.15 K.





ughh i cant get either one right!!Chemistry questions...please help!! any advice would be great!!?
so hard i am in grade 9 sorry can't help