Temperature Change

[705279989]

Why is the product rather than the reactant favored when a reaction is endothermic/ requires heat?

[705279989]

Also, why is the reactant formation favored when a reaction is exothermic?

[Kevin Xu 4F]

A reaction just by itself being endo or exothermic does not tell anything about whether or not it is product/reactant favored. However, when the temperature is raised or lowered, that would in effect shift the reaction in the direction that minimizes the gain/loss of heat appropriately. For example, if a reaction was endothermic, if the temperature was raised, it would shift to the right and be more product favored because it is trying to use up the extra heat in the reaction and endothermic reactions in the forward direction require heat. The same ideology works the same for an exothermic reaction.

[Bella Townsend]

Adding heat is like adding another reactant and when you increase the number of reactants the reaction shifts to the right.
Releasing heat is adding to the products side of the reactions, when you increase the products, the reaction shifts to the left.

[805394719]

The product is favored when the reaction is endothermic because the forward reaction requires the input of energy and that required energy is provided excessively by the increase in temperature. In endothermic reactions, the heat is on the reactants side since it is an input. Therefore, when the temperature increases, the reaction will shift to the right or the product side to balance the excess heat.

[Kavya Immadisetty 2B]

If the products require energy to be formed and the temperature increases, the forward reaction will be favored because the system will want to decrease the temperature. To do so, the reactants will react and absorb excess heat (because the forward reaction is endothermic). On the other hand, if the temperature is lowered, there isn't enough heat and the exothermic reaction will be favored. So if the reaction requires heat, the backwards reaction will be favored.

[Elizabeth Harty 1A]

Its temperature dependent

[KnarGeghamyan1B]

Think of heat as a reactant in endothermic reactions. When heat is added, its like the reactant side becomes overwhelmed, so the system needs to tip to the other side (products) to balance at equilibrium.

[VioletKo3F]

Since the reaction is endothermic, when the temperature is raised the reaction favors the products since it shifts to the right due to the reaction using up the heat to produce more products.

[Matthew Tsai 2H]

If a reaction is endothermic (requires heat), then addition of heat drives the reaction forward because the heat is used similarly to another reactant. The same concept applies if heat is removed, or also for exothermic reactions.