Which of the following transformations are endothermic? 1)The burning of a piece of wood in a fireplace. 2)The water vapor condensed into clouds. 3)As a result of a reaction, the products have more energy than the reactants. 4)The dry ice sublimated into carbon dioxide. 5)N2(g) + 3 H2(g) to 2 NH3(g) + 92 kJ 6)A change of state required heat.