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The equilibrium constant K for the first reaction is 6.83 x 10-12 at 1000 K

Jules Bruno
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Hey, guys, In this new video, we're gonna take a look at Hess's law. At least kind off. Now, we're gonna say that when it comes to Hess's law, we learned that the total entropy change. So total delta h of a reaction by taking into account each individual step. Now, we're gonna do the same exact thing. Except instead of using Delta H, we're gonna use our equilibrium, constant K. So they pay very close attention to what I do here for these two particular examples. Now we're gonna say the equilibrium constant for the reaction. This reaction here is 6.83 times 10 to the negative, 12 at 1000 Kelvin. Now I'm asking you to find a new K for this new reaction. Now, what you should realize here is that both of these reactions are the same. They both have CO two. They both have CEO. They both have 02 for the same exact equation. The only difference here is I changed and manipulated the one on the top so that it now looks like this one. So what we have to figure out is what changes that I do and what effect will that have on the equilibrium? Constant K. So we're gonna say first Co two was a reactant, but now it's a product. These guys were products. Now they're reacting. So it looks like I reverse the reaction and just realize when I reverse a reaction, K becomes the reciprocal. So K was 6.83 times 10 to the negative 12 while now it becomes 1/6 0.83 times to the negative 12 it becomes the reciprocal of whatever it waas. Now, that's one change that I did. The other change that I did. It looks like I multiplied by four. Because here this CO two has a four. Now, this CEO has a four now. And when we do four times a half the two councils out with this four and that's how we got this to here. Now, when you multiply by a number, that number becomes the power. So this is gonna become to the fourth. So it's gonna become 1/6 0.83 times 10 to the negative, 12 to the fourth. Okay, so when you multiply by number, it becomes a power. So what we're gonna do here is just solve for what's inside 1st. 1/6 0.83 times, 10 to the negative 12. That gives us 1.46 times 10 to the negative 11. Well, actually to the positive 11. And now that's to the fourth. So that's going to give me 4.60 times to the 44 don't. So that will be our answer here. So remember, if you reverse the reaction, then we're gonna say that becomes the reciprocal one over whatever. When we multiply by a number, that's gonna become the power you multiply by five, it becomes power five. Let's say we divided by a number. Let's say we divided by three. Well, just remember, if you're dividing by three, that is the same as multiplying by one third. And if you're multiplying by one third, then one third becomes the power, let's say you have to divide by two. If you're dividing by two, that's the same thing as multiply by a half. And in that way half becomes the power. Okay, so that's how we get around the dividing aspect of this