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

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In summary, the question is asking for the entropy change and heat transfer in a reaction at a temperature of 300K. Using the molar heat capacities of the reactants and products, the entropy change can be calculated as -1sqrt(T) and the heat transfer can be calculated as -1(sqrt300) * 300. This indicates that the reaction is exothermic, as heat is released. The lecture notes from MIT 5.60 explain that the heat capacity at constant pressure can be found by taking the derivative of enthalpy with respect to temperature. This can be used to calculate ∆Cp using the equation ∆Cp= ∑vCp (products) - ∑vCp (react
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quietrain
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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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Are you sure this is all the data there is?
 
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1. What is entropy and how does it relate to thermodynamics?

Entropy is a measure of the disorder or randomness in a system. In thermodynamics, it is a fundamental concept that describes the direction and extent of energy transfer during a physical or chemical process.

2. What is the difference between endothermic and exothermic reactions?

Endothermic reactions absorb heat from their surroundings, causing the temperature of the system to decrease. Exothermic reactions release heat into their surroundings, causing the temperature of the system to increase.

3. How can we calculate the change in entropy for a given reaction?

The change in entropy (ΔS) can be calculated using the equation ΔS = q/T, where q represents the heat transferred and T is the temperature in Kelvin.

4. Can the change in entropy be negative?

Yes, the change in entropy can be negative. This indicates that the system has become more ordered or less random during the process.

5. How does increasing temperature affect the change in entropy?

An increase in temperature typically leads to an increase in the change in entropy for a given reaction. This is because higher temperatures increase the amount of energy available for disordering the system.

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