Calculate ΔSsurr for the following reactions at 25^∘ C and 1 atm. a. C3 H5(g)+5 O2(g) ⟶3 CO2(g)

step 1 Hi guys in problem 38 we are asked to calculate the entropy of the surrounding at 25 degrees cen

Calculate ΔSsurr for the following reactions at 25^∘ C and...

Calculate $\Delta S_{\text {surr }}$ for the following reactions at $25^{\circ} \mathrm{C}$ and 1 atm. a. $\mathrm{C}_{3} \mathrm{H}_{5}(g)+5 \mathrm{O}_{2}(g) \longrightarrow 3 \mathrm{CO}_{2}(g)+4 \mathrm{H}_{2} \mathrm{O}(t) \Delta H^{\circ}=-2221 \mathrm{~kJ}$ b. $2 \mathrm{NO}_{2}(g) \longrightarrow 2 \mathrm{NO}(g)+\mathrm{O}_{2}(g)$ $\Delta H^{\circ}=112 \mathrm{~kJ}$

Calculate $\Delta S_{\text {surr }}$ for the following reactions at $25^{\circ} \mathrm{C}$ and 1 atm.
a. $\mathrm{C}_{3} \mathrm{H}_{5}(g)+5 \mathrm{O}_{2}(g) \longrightarrow 3 \mathrm{CO}_{2}(g)+4 \mathrm{H}_{2} \mathrm{O}(t) \Delta H^{\circ}=-2221 \mathrm{~kJ}$
b. $2 \mathrm{NO}_{2}(g) \longrightarrow 2 \mathrm{NO}(g)+\mathrm{O}_{2}(g)$
$\Delta H^{\circ}=112 \mathrm{~kJ}$

Key Concepts

Entropy Change of the Surroundings

This concept relates to how the entropy (a measure of disorder or randomness) of the surroundings changes when a system undergoes a chemical or physical process. In many thermodynamic problems, especially under constant temperature conditions, calculating the entropy change of the surroundings is crucial for determining the overall spontaneity of a process by analyzing the total entropy change of the universe.

Relationship Between Enthalpy Change and Surroundings’ Entropy

Under conditions of constant pressure and temperature, the change in the entropy of the surroundings can be calculated using the relation ?S_surroundings = -?H/T. This formula arises because the heat exchanged with the surroundings (represented by the enthalpy change, ?H) is absorbed or released by a large thermal reservoir, meaning the entropy change of the surroundings is directly proportional to the negative of the system’s enthalpy change divided by the absolute temperature.

Temperature Conversion to Kelvin

For calculations in thermodynamics involving absolute temperatures, it is essential to convert temperatures from degrees Celsius to Kelvin. This conversion is performed by adding 273.15 to the Celsius temperature, ensuring that temperature-dependent calculations such as entropy change using ?S = -?H/T are accurately evaluated with the correct absolute temperature.

Transcript

Please give Ace some feedback