textbook 5.35
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Re: textbook 5.35
I believe the solution manual states that the answer to part a would be: 2A --> B + 2C.
According to the graph, looking at the changes in pressure from initial state to equilibrium, ΔA = 10, ΔB=5, and ΔC=10.
From this, the ratio of change in A:B:C would be 2:1:2. This ratio then provides the coefficients for the reactants and products in the equation and since this is decomposition of A into B and C, the equation would be 2A --> B + 2C.
According to the graph, looking at the changes in pressure from initial state to equilibrium, ΔA = 10, ΔB=5, and ΔC=10.
From this, the ratio of change in A:B:C would be 2:1:2. This ratio then provides the coefficients for the reactants and products in the equation and since this is decomposition of A into B and C, the equation would be 2A --> B + 2C.
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Re: textbook 5.35
I was also wondering this, but the relative ratios of change (delta) creates the 2:1:2 pattern.
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Re: textbook 5.35
Ritika Prasad 1A wrote:I believe the solution manual states that the answer to part a would be: 2A --> B + 2C.
According to the graph, looking at the changes in pressure from initial state to equilibrium, ΔA = 10, ΔB=5, and ΔC=10.
From this, the ratio of change in A:B:C would be 2:1:2. This ratio then provides the coefficients for the reactants and products in the equation and since this is decomposition of A into B and C, the equation would be 2A --> B + 2C.
Hey Ritika, this description was super helpful to me! I was just focused on those end values, which clearly are pretty weird. Sorry for dredging up your post from over a month ago and it's ok if you can't answer this question, but do we use the end values the reaction plateaus on for our K value? Even with the new coefficients, my K value doesn't quite match what the book has, so I feel like I'm still messing something up.
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Re: textbook 5.35
allyssa bradley 1H wrote:
Hey Ritika, this description was super helpful to me! I was just focused on those end values, which clearly are pretty weird. Sorry for dredging up your post from over a month ago and it's ok if you can't answer this question, but do we use the end values the reaction plateaus on for our K value? Even with the new coefficients, my K value doesn't quite match what the book has, so I feel like I'm still messing something up.
Hey Allyssa! I'm glad that explanation helped! For the K value, yes, I believe you would use the end values because those are the values at equilibrium, so K = [(Partial Pressure of B)*(Partial Pressure of C)^2]/[(Partial Pressure of B)^2] so in simplified form: K = [(B)(C^2)]/[(A^2)].
Since we're not given exact values at the end, we can estimate from the graph that the partial pressure of A is 18, C is 10, and B is 5.
In the solution manual, I believe the values are divided by 100 because the y-axis scale is P/kPa, and standard atmospheric pressure (or 1 atm) is defined as 101.325 kPa.
So then finally, you get [(5/100)*(10/100)^2]/[(18/100)^2] = 1.54 x 10^-2, which matches the solution in the manual! I hope that helps :)
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