For the reaction

Jules Bruno
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So now that we've seen example one, let's take a look. At example, too. So, for example, to were saying for the reaction and two plus 02 giving us to 102 gas, we have our delta G R first Delta G equal to 75,550 jewels over moles at that temperature of 1 75 Calvin. And then we're gonna have a second Delta G equal to 41,875 jewels over moles at 225 Kelvin's. So it's asking us calculate Delta S and Delta H for the reaction. So this is what we gonna do for this particular one? Since we're dealing with two types of Delta G here, we're gonna say Delta G equals Delta H zero minus t Delta s zero. That will be for our first Delta G values. But remember, I gave you a second one. So we're gonna say minus delta G zero equals Delta H zero minus t Delta s zero. Now that negative sign is gonna get distributed toe everything within the brackets. So it becomes now. And since we're gonna need some room to do these calculations, guys, I'm going to remove myself from the image so we have more room to work with. So we're gonna now plugging what we know we have 75,550 for one Delta G in that equals Delta H minus 1 75 Calvin times, Delta s minus 41,000, 875. Remember, this negative gets distributed. Okay, so this delta H now becomes negative. Delta H here. We had a negative sign. A negative times a negative. Gives me a positive the Delta H values. Now cancel out. Then we're gonna get 33,000, 675 equals 50 times Delta s We want his delta s. So we divide by 50 Calvin on both sides. So now Delta s equals 6 73. Jules over moles, times K. So that will be our entropy value. Now, if we want to find Delta H, we simply now do. Delta G zero equals Delta H zero minus t Delta s zero. We can choose either one of these Delta G values Doesn't really matter which one we choose. So we're gonna say 75,550 equals Delta 80 which we're looking for minus 1 75 Kelvin times the six. 73 5 jewels over moles times K we calculated from earlier. Okay, now, when you multiply these two together, it's gonna give you 117863 The Calvin's canceled out so the units will be left jewels of Rommel's. So we're gonna add 117863 to both sides. So that's gonna give us at the end. Delta H zero equals 1. times 10 to the five Jules over moles. So this is what the technique you should approach when they give you two Delta jeez to temperatures and they ask you basically to find Delta S and Delta H. This is the exact method that you should use.