Statement I: When the temperature of a reaction at equilibrium is increased, the equilibrium will shift to favor the endothermic direction
Because
Statement II: Endothermic reactions involve heat acting as a reactant and Le Chateliers principle states that an equilibrium shift will occur to offset temperature changes
Le Châtelier's principle states that a change in temperature, pressure, or concentration of reactants in an equilibrated system will stimulate a response that partially off-sets the change to establish a new equilibrium. In the case of changing temperature, adding or removing of heat shifts the equilibrium.
The Heat of Reaction is the change in the enthalpy of a chemical reaction. In endothermic reactions, ( ΔH>0 ) heat is absorbed with the reactants. For example, more energy is needed to overcome the forces of attraction between molecules and to separate them from one another (the activation energy) than the energy gained when new bonds are formed.
In exothermic reactions, (ΔH<0 ) heat is released with the products. When separated molecules join together, enough energy is released to overcompensate for the energy required to break reactant bonds. In this chemical reaction