We will ask a chain of questions again about Chapter 17 and thermodynamics! First person, answer my question, then ask your own. Continue on in this fashion.
A chemical reaction has an decrease in entropy and is exothermic. Is this reaction always spontaneous, never spontaneous or explain the impact of temperature on the spontaneity?
Since the change in enthalpy and entropy are negative that means the reaction can be spontaneous at low temperatures.
ReplyDeleteEntropy contributes to what in the universe and give an example.
Well, for every spontaneous reaction, the entropy of the universe increases. An example of this would be methane burning in an oxygen rich environment.
ReplyDeleteQ: What is the relationship between the equilibrium constant and free energy?
The relationship between the equilibrium constant and free energy is seen through the equation delta G = -RT ln K. If the amount of free energy is negative, then the equilibrium constant is positive and products are favored.
ReplyDeleteQuestion: Which state of matter typically has the highest entropy and why?
Gas phase will have the highest entropy because entropy is about disorder and the more disordered the molecules, the higher the entropy.
ReplyDeleteQuestion: if entropy is favourable and enthalpy in not favrouble or the opposite, then how do we figure out if th reaction is spontanous or not.
The reaction would be spontaneous at higher temperatures (which is when delta G agrees with the sign of delta S), but not at lower temperatures (where delta G agrees with the sign of delta H).
ReplyDeleteQuestion: For the following reaction, would the entropy change be positive (favorable) or negative (unfavorable)?
SO3 (g) + H2O (l) ----> H2SO4 (l)
For this reaction, by the delta S = sum of the products - sum of the reactants, the entropy change is negative and is considered unfavorable and would lean towards a nonspontaneous reaction.
ReplyDeleteQuestion: if the enthalpy is favorable and the entropy is unfavorable how would you determine whether or not the reaction is spontaneous?
You would examine the reaction at high and low temperatures to see at which the reaction is spontaneous. When employee is favorable typically the reaction is spontaneous at low temperatures.
ReplyDeleteWhat data do you need to calculate the minimum temperature for which a reaction is spontaneous at standard conditions?
"employee" => enthalpy (darn autocorrect!)
ReplyDeleteThanks for your responses!
ReplyDelete