When H and S are both positive
if H and S are both negative
If H and S are both negative
∆G = ∆H - T∆S and for it to be spontaneous, ∆G should be negative. If both ∆H and ∆S are positive, in order to get a negative ∆H, the temperature needs to be elevated in order to make the ∆S term greater than the ∆H term. So, I guess the answer would be "the higher the temperature, the more likely will be the spontaneity of the reaction."
Use the following equation: delta G = delta H - T*deltaS. A reaction is spontaneous if delta G is negative. A reaction will always be spontaneous (under any temperature) only if the change in enthalpy (delta H) is negative and the change in entropy (delta S) is positive. If this is not the case, the reaction will only be spontaneous (negative delta G) for a range of temperatures (or could be always non-spontaneous)
The reaction is exothermic.
The reaction is exothermic.
the reaction is exothermic
The reaction is endothermic.
This is an endothermic chemical reaction.
No, when H and S are both negative, the reaction will only be spontaneous below a certain temperature
It can be said to be exothermic since H is negative. Also below a temp of 3708ºC, the reaction will be spontaneous because ∆G will be negative. This is from ∆G = ∆H - T∆S.
If the ∆H is positive and the ∆S is positive, then the reaction is entropy driven. If the ∆H is negative and the ∆S is negative, then the reaction is enthalpy driven. If ∆H is positive and ∆S is negative, then the reaction is driven by neither of these. If ∆H is negative and ∆S is positive, then the reaction is driven by both of these.
∆G = ∆H - T∆S and ∆G has to be negative for the reaction to be spontaneous. So, ultimately the effect of temperature will depend on the value of ∆H. If ∆H is negative, and ∆S is positive, then temperature won't matter, and reaction will be spontaneous. If ∆H is positive, and ∆S is positive, then a high temperature will favor spontaneity. If ∆H is negative and ∆S is negative, then a low temperature will favor spontaneity. So, the answer to your question is the higher the temperature the more likely the reaction will occur spontaneously.
In science, Gibbs free energy can tell if a chemical reaction is spontaneous. It is given by the formula: G = H - TS H = enthalpy of reaction S = entropy of reaction T = temperature in Kelvin If G is negative the reaction is spontaneous. However if activation energy is high, reaction rate is slow and the reaction may take a while to progress, regardless of its spontaneity.
When H and S are both positive
if H and S are both negative