in this video, we're gonna review the second law of thermodynamics. So the second law of thermodynamics can be phrased and stated in so many different ways to mean the same thing. And all it's really saying is that 100% efficient energy conversion or transferring all of the energy of one form into a different form is impossible because thermal energy for heat is lost with every energy transfer. And this heat that's lost increases the universal entropy or the entropy of the surroundings. Now the second law of thermodynamics also states that all spontaneous processes increase universal entropy as they proceed towards a state of equilibrium or minimal potential energy. And we'll talk Maura about equilibrium in some of our later videos. Now recall from our previous videos that even though the universe is increasing in entropy, that doesn't mean that local entropy cannot decrease. So local entropy or the entropy of a system that we're focusing on, can decrease as long as it's offset by an increase in universal entropy eat. And that's important to remember so that you guys know that the second law of thermodynamics is not broken. And so if we take a look at our example of the second law of thermodynamics over here on the left, we have a large amount of energy that's available represented by this large arrow. And so notice that at the point of energy conversion that not all of the energy is transferred. So 100% efficient energy conversion is not possible. And so there's a smaller amount of energy that's transferred at the point of energy conversion represented by this dotted line. And so the energy that is not transferred is lost in the form of heat. And so this heat that's lost or this thermal energy that's lost increases the universal entropy and so all spontaneous processes release heat and increase the universal entropy. And we'll talk more about this as we talk about our ex organic and inorganic processes in our next video. So I'll see you guys, then

so recall from your previous chemistry courses that spontaneous processes are extra. Gone IQ processes with a negative delta G value and all spontaneous processes occur without outside intervention, meaning that there's no need for an energy input for these processes to occur. And be careful not to confuse. Spontaneous with fast. So spontaneous does not mean fast, and there are spontaneous processes that occur very, very slowly and so again, recall that spontaneous just means that they will eventually occur without any outside intervention. Now, spontaneous processes are associated with Cata Bolic Processes and Cata Bolic processes break down materials so they take a single, larger substance. And they break it down into multiple smaller substances, increasing the disorder and increasing the entropy. And so because there's an increase in entropy, these are thermo, dynamically favorable processes. Now, non spontaneous processes are the complete opposite of spontaneous processes, and non spontaneous processes noticed that they are undergone IQ. They have a positive delta G value and they require outside intervention, so they need some kind of energy input in order to proceed. Now, non spontaneous processes are associated with anabolic processes or processes that build up materials, so they take multiple smaller substances, and they link them together to create a single, larger substance, which decreases the local entropy. And because there's a decrease in the local entropy, these are thermo dynamically unfavorable. So they're not favorable now, as we mentioned several times in our previous videos, anabolic processes and, uh, non spontaneous processes. Although they decrease the local entropy, they're still accompanied by an overall increase in the universal entropy and so universal entropy is gonna increase with both X organic and inorganic processes. So let's take a look at our example below to clear that up. And so what we've got here is the classic graphs for X organic and inorganic reactions that you guys, I'm sure are very familiar with. And so, on the left, we have our ex organic reactions and notice that the reactant have a higher free energy than the products, and they they have a negative Delta G value. So the change in Gibbs free energy from products to react there's a decrease and that free energy. And so, uh, there's gonna be energy that is released so text organic reactions release energy into the environment and have a negative Delta G value Now over here with our end organic reaction notice that the reactant have lower energy than the products. And so because of that, the products have mawr energy and there was an increase in the change in energy. So the there's a positive delta g value and that means that the energy was absorbed from the environment. Now, what you also should notice is that we have these three other arrows here double arrows which represent essentially alternate y axes. So you have multiple y axes here, so notice that the reactant up here, which have higher energy, are associated with an unstable system, low local entropy and an ordered system. And so are the products of the end organic reactions. So thes air all associated with these higher things. And then down here, the products of extra Connick reactions which have lower energy so lower energy is associated with a more stable system, hire local entropy and mawr disordered system, and so are the reactant of the inorganic reactions. So you can see this is how the associations occur now with an ex organic process notice that we're going from up high to down low. So for the X organic process. We're going in this direction so an arrow from top to bottom and so X organic processes in, uh, increase the stability of the system. They increase the entropy, the local entropy and they increase the disorder of the system. Now this is because they are cata bolic processes. Now the opposite is true for end organic process. Notice that we're going from low energy reacting to the high energy products. So we're going in the opposite direction, going in this direction for Ender Connick processes. And so an organic processes have an unstable system. They create an unstable system with their products, they decrease the local entropy and they increase the order of the system. And even though there's a decrease in the local entropy with an organic reactions, we know that the overall universal entropy is still going thio increase and so X organic and inorganic processes are both still associate it with an increase in the universal entropy. And so this is important toe Keep in mind as we move forward in our biochemistry course, and this is a good summary of the differences between X organic and inorganic processes, and I'll see you guys in our practice videos