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H 2 ( g ) + I 2 ( g ) 2 H I ( g )
Q P H I 2 P H 2 P I 2

It is important to note that the partial pressures in Q need not be the equilibrium partial pressures. However, if the pressures in Q are the equilibrium partial pressures, then Q has the same value as K p , the equilibrium constant, by definition. Moreover, if the pressuresare at equilibrium, we know that Δ G 0 . If we look back at [link] , we can conclude that

Δ G ° R T K p

This is an exceptionally important relationship, because it relates two very different observations.To understand this significance, consider first the case where Δ G ° 0 . We have previously reasoned that, in this case, the reactionequilibrium will favor the products. From [link] we can note that, if Δ G ° 0 , it must be that K p 1 . Furthermore, if Δ G ° is a large negative number, K p is a very large number. By contrast, if Δ G ° is a large positive number, K p will be a very small (though positive) number much less than 1. In this case, the reactants will be strongly favored atequilibrium.

Note that the thermodynamic description of equilibrium and the dynamic description of equilibrium arecomplementary. Both predict the same equilibrium. In general, the thermodynamic arguments give us an understanding of the conditionsunder which equilibrium occurs, and the dynamic arguments help us understand how the equilibrium conditions are achieved.

Review and discussion questions

Each possible sequence of the 52 cards in a deck is equally probable. However, when you shuffle a deck and thenexamine the sequence, the deck is never ordered. Explain why in terms of microstates, macrostates, and entropy.

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Assess the validity of the statement, "In all spontaneous processes, the system moves toward a state of lowestenergy." Correct any errors you identify.

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In each case, determine whether spontaneity is expected at low temperature, high temperature, any temperature, orno temperature:

Δ H ° 0 , Δ S ° 0

Δ H ° 0 , Δ S ° 0

Δ H ° 0 , Δ S ° 0

Δ H ° 0 , Δ S ° 0

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Using thermodynamic equilibrium arguments, explain why a substance with weaker intermolecular forces has agreater vapor pressure than one with stronger intermolecular forces.

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Why does the entropy of a gas increase as the volume of the gas increases? Why does the entropy decrease as thepressure increases?

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For each of the following reactions, calculate the values of Δ S ° , Δ H ° , and Δ G ° at T 298 K and use these to predict whether equilibrium will favor products or reactants at T 298 K . Also calculate K p .

2 C O ( g ) + O 2 ( g ) 2 C O 2 ( g )

O 3 ( g ) + N O ( g ) N O 2 ( g ) + O 2 ( g )

2 O 3 ( g ) 3 O 2 ( g )

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Predict the sign of the entropy for the reaction 2 H 2 ( g ) + O 2 ( g ) 2 H 2 O ( g ) Give an explanation, based on entropy and the Second Law, of why this reaction occurs spontaneously.

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For the reaction H 2 ( g ) 2 H ( g ) , predict the sign of both Δ H ° and Δ S ° . Should this reaction be spontaneous at high temperature or at lowtemperature? Explain.

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For each of the reactions in [link] , predict whether increases in temperature will shift the reaction equilibrium more towardsproducts or more towards reactants.

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Using [link] and [link] , show that for a given set of initial partial pressures where Q is larger than K p , the reaction will spontaneously create more reactants. Also showthat if Q is smaller than K p , the reaction will spontaneously create more products.

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Questions & Answers

A golfer on a fairway is 70 m away from the green, which sits below the level of the fairway by 20 m. If the golfer hits the ball at an angle of 40° with an initial speed of 20 m/s, how close to the green does she come?
Aislinn Reply
cm
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A mouse of mass 200 g falls 100 m down a vertical mine shaft and lands at the bottom with a speed of 8.0 m/s. During its fall, how much work is done on the mouse by air resistance
Jude Reply
Can you compute that for me. Ty
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what is inorganic
emma
Chemistry is a branch of science that deals with the study of matter,it composition,it structure and the changes it undergoes
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chemistry could also be understood like the sexual attraction/repulsion of the male and female elements. the reaction varies depending on the energy differences of each given gender. + masculine -female.
Pedro
A ball is thrown straight up.it passes a 2.0m high window 7.50 m off the ground on it path up and takes 1.30 s to go past the window.what was the ball initial velocity
Krampah Reply
2. A sled plus passenger with total mass 50 kg is pulled 20 m across the snow (0.20) at constant velocity by a force directed 25° above the horizontal. Calculate (a) the work of the applied force, (b) the work of friction, and (c) the total work.
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you have been hired as an espert witness in a court case involving an automobile accident. the accident involved car A of mass 1500kg which crashed into stationary car B of mass 1100kg. the driver of car A applied his brakes 15 m before he skidded and crashed into car B. after the collision, car A s
Samuel Reply
can someone explain to me, an ignorant high school student, why the trend of the graph doesn't follow the fact that the higher frequency a sound wave is, the more power it is, hence, making me think the phons output would follow this general trend?
Joseph Reply
Nevermind i just realied that the graph is the phons output for a person with normal hearing and not just the phons output of the sound waves power, I should read the entire thing next time
Joseph
Follow up question, does anyone know where I can find a graph that accuretly depicts the actual relative "power" output of sound over its frequency instead of just humans hearing
Joseph
"Generation of electrical energy from sound energy | IEEE Conference Publication | IEEE Xplore" ***ieeexplore.ieee.org/document/7150687?reload=true
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what are the types of wave
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answer
Magreth
progressive wave
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Mujahid
A string is 3.00 m long with a mass of 5.00 g. The string is held taut with a tension of 500.00 N applied to the string. A pulse is sent down the string. How long does it take the pulse to travel the 3.00 m of the string?
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Source:  OpenStax, General chemistry ii. OpenStax CNX. Mar 25, 2005 Download for free at http://cnx.org/content/col10262/1.2
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