WEBVTT
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Hi guys. So in problem 50 we are acts
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to predict the sign on calculate. Be stunned,
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that intro piece for the following reactions. So let's
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start with the 1st 1 Just say to predict the
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entropy for the 1st 1 we look at be reactant
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ce on the products. So moving from the accent
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to the product, I'm running from gushes face to
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liquid face. I want that doors is to decrease
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. Did this orderliness of this system on By so
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doing, we're decreasing the entropy so they can trapeze
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. Negative. So let's calculate that to calculate that
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we know that entropy is a state function, which
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means it depends only on the initial on final states
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of this system. So we have the sum of
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the entropy is off the product. My nose this
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summer, Offifty trapeze off the reactant ce so can
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look up cool. The entropy is off each off
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d involved in species from this ton Dad tables pretty
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much any at the back off. Any physical chemistry
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textbook this ah standards. I'm here tabulated. I
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bet you can find them on appendix. So for
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the product in this case, we have just one
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so which is 70. Um, forgive me.
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So we need to include the most. So,
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how many Morse off the product we have this one
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, right? So we have one more off that
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which is off water. All right, I'm a
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toss. 17 Joe Kelvin. Mole minus one more
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off hydrogen. Right. Got this is the liquid
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. We should indicate the state's a swell. This
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is gas, which has to go file you carving
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mall. So this is plus how more off oxygen
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on oxygen House one for everyone. Ju Park children
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more. So in each case, the more I
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can slot. In each case, the more counts
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watch, right? And then when you do this
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, you we'll get negative 1 64 ju park calving
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doesn't wall is gone, so you can see that
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we predict it. Delta asked to be negative,
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and it was a sneaky too. So let's look
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at this second, uh, problem. The second
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problem has gases in both reactant on park site.
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So everything and this system is gashes. Both reactions
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on part. In that case, you someone the
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the most of it rattles and then some more off
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the product and compare So here we have two plus
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three, just five miles. Oh, gashes molecules
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on here. We have to pose for six months
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of guy his molecules. So because we have more
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Moors Oh guy, shal smaller, close in product
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side. It means that it's an increase. And
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this older Dennis off the system on his doctors,
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it's positive. Yes, this increased. So that
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is the prediction. It's Louis. Say, Mom
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, See? We'll get Remember we said Delta S
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is We're going by the summation off the entropy is
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off to product minus summation of the entropy of the
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reacted. So the entropy of the product starting with
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Come on, fog side now. True moles.
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Oh, see. Or two Ben. So to
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house to one full. When my dean it is
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Jew children more. We're all of them. So
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I mean, not show them all. What do
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you know? It is the same, sir.
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Plus what this is for, um, for malls
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off water. What gas? What? Bye bye
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. One. It's nine. Jew by Kelvin Moore
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. All right, My house. No, not
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off reactant. We have two moles. Oh,
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me, fennel, Cass. And that will be
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so fine. Right? Your fork over. No
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, Oh, oh, Class through Moore's excision,
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guys. Um, so I think the but off
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eternal ISS 2 40 In this case, Yeah,
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it's to 40. I'm not of oxygen is too
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awful to a fire. So 2 14 and then
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the oxygen is two Fire Joe Pa Kelvin Moore.
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So again, the more councils are no, councils
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are no. Councils are most council. So when
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you compute four, the daughter s here. You
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have 89 Jule Barcoding. We just positive as predicted
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here. Right. So finally here We're moving from
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Gashes State two I, as a solution clearly were
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decreasing. Did this orderliness off this system? And
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since we're decreasing the this orderliness off the system Dota
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is well Okay, negative again. Delta is Is
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the submission off the It's off. T minus a
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mission of this off our right. We're pee on
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our product and reactant respectively. And we have in
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this case, one more off. It was accused
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, and it has entropy off zero. All right
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, Plus, we have, well, more off
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. Cool, right? I am a curious which
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has entropy off 57 Jew of in more minus.
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We have the entropy off. How's you chloride gas
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, which is one more I've dredging. Cool,
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right Gas hiss 1 87 Jew. Wow, Kelvin
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, No. Right. So more goes with more
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No counselors out. The more I hear clearly,
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this is zero. So you don't even need to
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come up with anything, then the small councils of
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this. So you be left with this. So
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when you compute for this, you have this number
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. Community 1 30 Jewels are killing. Well predicted
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, designed to be negative. And it's negative.
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So this is how you predict the sign? I'm
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the calculate the entropy off any given system provided,
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you know, the equation of the reaction. I'm
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the state's off the species involved in the reaction.