![]() In this case, it is the opposite of that of entropy, the negative sign represents a spontaneous process. By finding the sign of it alone we are able to predict whether a phenomenon will happen spontaneously or not. Calculating the net change in entropy is very tedious and hence we devise a new function, called Gibbs Free energy, which is a property of the system and easy to calculate. Net entropy change of a universe is given by $\Delta S= \Delta S_$. Yes, I agree that entropy of the system (water) decreases but it happens that at STP the entropy of the universe (the water and its immediate surroundings) have a net increase in entropy. ![]() I reply that you didn't read the statement correctly it is written the entropy of the universe and not of the system. Now you may object by saying that why does water freezes spontaneously at STP? After all the entropy of ice is less than that of water hence there is a decrease in entropy of the system, hence this should not be spontaneous. Many plastic materials are organic polymers that contain carbon and hydrogen. Under what conditions does G allow us to predict whether a process is spontaneous arrowforward. A phenomenon will happen spontaneously if the entropy of the universe is positive and won't happen if it is negative or zero (again, spontaneously). Explain (a) why the entropy increases and (b) why under most circumstances, a decrease in volume results in an entropy decrease. You need to clear the difference in entropy of the system and the universe. (It’s not a perfect analogy but it serves to show my thinking). Then, the lower energy state would be at the bottom of the well, but then, apparently, with higher entropy. I am seeing the changes of state (in this example) to be like a potential well, where energy needs to be added to move the substance out of the well and change its state. Perhaps I am visualising this problem in the wrong way. losing energy, however, this contradicts the entropy conclusion. If I think of a gas, if would seem to me that a more stable arrangement is becoming a liquid i.e. I am unfamiliar with systems that are more stable at higher energy levels. When ∆S is positive, we are increasing the energy of the system, but apparently also making it more stable. When I see that ∆S is positive for an increase in entropy, that confuses me. ![]() My last point was going to be: an increase in entropy is an increase in energy, although this isn’t explicitly stated. A reaction is (more) feasible if it involves an increase in entropy.A system is more energetically stable when at a higher entropy.My notes (I am taking A-Level Chemistry) say the following things: Astronomer Arthur Eddington pioneered the concept of the Arrow of Time in 1927. It is the non-reversible process wherein entropy increases. ![]() The Arrow of Time is a name given to the idea that time is asymmetrical and flows in only one direction: forward. When it comes to defining entropy in terms of energy, though, I am slightly confused. Entropy is one of the few concepts that provide evidence for the existence of time. My understanding of the basics of entropy are as follows: there are more ways for a system to be arranged in a disordered state, than an ordered state. ![]()
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