Question

18)State if the Entropy change for each of the following is positive or negative. How will entropy change with increased temp?

2 C₄H₁₀ + 9 O₂ ====è 4 CO₂ + 10 H₂O (all gas)

CO₂ (solid) ==è CO₂ gas

MgCO₃ (solid) ====è MgO (solid) + CO₂ (gas)

Please show all work and how you arrive at the answer.

Answer 1

entropy of gas > entropy of aqueous > entropy of liquid > entropy of solid

in A entropy increases as reactant has less gases.

So, delta S is positive

in B entropy increases as reactant has less gases.

So, delta S is positive

in C entropy increases as reactant has less gases.

So, delta S is positive

For all of them, entropy change is positive

With increasing temperature, entropy increases.

this is because, as temperature increases, vibration increases and hence randomness increases. this increases the entropy