For which of the following will delta S be the most positve?
A) Co2(g)->CO2(s)
B) C6H12O6 (s)+ 6 O2(g) -> 6 Co2(g) + 6H20(g)
C) Na(aq) + Cl (aq)-> NaCl (s)
D) Cl2(g) + H2(g) -> 2HCl(g)
E) H(aq) + OH(aq) -> H20 (l)
I would go with b.
To determine which reaction will have the most positive ΔS (change in entropy), we need to consider the factors that affect entropy in each reaction.
Entropy is a measure of the randomness or disorder in a system. Generally, reactions that increase the number of particles or increase the randomness of particles will have a positive ΔS.
Let's analyze each reaction:
A) CO2(g) -> CO2(s)
In this reaction, CO2(g) is converting to CO2(s), which results in a decrease in the number of gas particles. As a solid, CO2 is more ordered and less random than a gas. Therefore, this reaction will have a negative ΔS.
B) C6H12O6(s) + 6O2(g) -> 6CO2(g) + 6H2O(g)
In this reaction, a solid (s) and multiple gas (g) particles are being formed from a solid and gas reactants. The number of gas particles is increasing, and the system becomes more random. Consequently, this reaction will have a positive ΔS.
C) Na(aq) + Cl(aq) -> NaCl(s)
In this reaction, ions in solution are combining to form a solid salt. While the number of particles decreases as ions come together to form a solid, the random arrangement of ions in solution is replaced by a more ordered arrangement of ions in the solid. Thus, this reaction will have a negative ΔS.
D) Cl2(g) + H2(g) -> 2HCl(g)
In this reaction, two gas molecules react to form a diatomic gas molecule. The number of gas particles remains the same, but the arrangement of particles changes from two separate molecules to a single molecule. Overall, this reaction does not introduce significant randomness, so it will have a small or negative ΔS.
E) H(aq) + OH(aq) -> H2O(l)
In this reaction, two aqueous solutions combine to form liquid water. The number of particles decreases, but the randomness does not change significantly. Therefore, this reaction will have a small or negative ΔS.
Based on the analysis, the reaction with the most positive ΔS is option B, C6H12O6(s) + 6O2(g) -> 6CO2(g) + 6H2O(g).