Help with Entropy Homework: A+B to D, Heat & Exothermic?

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The discussion focuses on calculating the entropy change and heat transfer for the reaction A + B → D at 300K. The user attempts to determine the entropy change using the equation change in s = ∫ Cp dT / T but is unsure about the temperature limits. They conclude that since the heat capacities equalize at a certain temperature, they can simplify the calculation. The resulting heat transfer calculation indicates that the reaction is exothermic, as heat is released. The conversation references MIT lecture notes to support the calculations and methodology.
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Homework Statement


if i have reaction A + B --> D

if i produce 1 mol of D, what is the entropy change?
how much heat is transferred?
is this exothermic or endothermic?

Homework Equations



reaction carried out at T = 300K,

molar heat capacities(constant Pressure),

CA = 5sqrt(T)
CB = 8sqrt(T)
CD = 12sqrt(T)

The Attempt at a Solution



change in s = ∫ dQ / T right?

so ∫ Cp dT /T

but what are my limits for my Temperature?

is it right to say since they equalize at some temperature, i don't need to know my upper bound?

so i take CD - (CB + CA) to get -1sqrt(T) ?

so Q = CpT = -1(sqrt300) * 300

so since it is -ve, heat is released, and reaction is exothermic?

thanks
 
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