When 1 mol of gas is heated at constant volume temperature is raised from 298 to 308 K. Heat supplied to the gas is 500 J. Then which statement is correct ?

PbO₂  $$ \to $$ PbO; $$\Delta $$G₂₉₈ < 0
SnO₂ $$ \to $$ SnO;  $$\Delta $$G₂₉₈ > 0

Most probable oxidation state of Pb and Sn will be

For the reaction,
C₂H₅OH_(l) + 3O_2(g) $$ \to $$ 2CO_2(g) + 3H₂O_(l)
which one is true

2Zn + O₂ $$ \to $$ 2ZnO;  $$\Delta $$G^o = $$-$$ 616 J
2Zn + S₂ $$ \to $$ 2ZnS;  $$\Delta $$G^o = $$-$$ 293 J
S₂ + 2O₂ $$ \to $$ 2SO₂;   $$\Delta $$G^o = $$-$$408 J
$$\Delta $$G^o for the following reaction
2ZnS + 3O₂ $$ \to $$  2ZnO + 2SO₂ is