Question

In: Chemistry

Calculate ΔS°(universe) for the decomposition of 1 mol of gaseous phosphine (PH3) to form white phosphorus...

Calculate ΔS°(universe) for the decomposition of 1 mol of gaseous phosphine (PH3) to form white phosphorus and gaseous hydrogen at 25 °C.

Solutions

Expert Solution

PH3 (g) ---------------> P (white ) + 3 /2 H2 (g)

ΔS° system = ΔS° products - ΔS° reactants

                      = ( 164.4 + 3/2 * 223.1 ) - 210.2

                      = 288.85 J / K

                   

ΔH°   = (0 + 3/2 * 0 ) - 5.4

          = -5.4 kJ / mole

T = 273 + 25 = 298 K

ΔS°surr = - ΔH° / T

               = 5.4 x 1000 / 298

              = 18.12 J / K

ΔSo universe = ΔS° system + ΔS°surr

                      = 288.85 + 18.12

                     = 307 J / K

ΔSo universe = 307 J / K


Related Solutions

How many grams of phosphine (PH3) can form when 44.4 g of phosphorus and 98.8 L...
How many grams of phosphine (PH3) can form when 44.4 g of phosphorus and 98.8 L of hydrogen gas react at STP? P4(s) + H2(g) → PH3(g) (Unbalanced)
Phosphine (PH3) decomposes into phosphorus and molecular hydrogen: 4PH3(g) → P4(g) + 6H2(g) Experiments show that...
Phosphine (PH3) decomposes into phosphorus and molecular hydrogen: 4PH3(g) → P4(g) + 6H2(g) Experiments show that this is a first-order reaction, with a rate constant of 0.0173 s-1 at 650°C. Identify each of the following statements about this reaction as true or false. (Use the drop-down menu and select "True" or "False" for each. You must get all 4 correct.) The reaction PH3 → PH2 + H might be the rate-determining step in the mechanism of this reaction. The rate...
Phosphine (PH3) decomposes into phosphorus and molecular hydrogen: 4PH3(g) → P4(g) + 6H2(g) Experiments show that...
Phosphine (PH3) decomposes into phosphorus and molecular hydrogen: 4PH3(g) → P4(g) + 6H2(g) Experiments show that this is a first-order reaction, with a rate constant of 0.0173 s-1 at 650°C. Identify each of the following statements about this reaction as true or false. (Use the drop-down menu and select "True" or "False" for each. You must get all 4 correct.) True/False  The mechanism for this reaction must involve two or more elementary steps. True/False  The activation energy for the reaction cannot be...
the density of a gaseous fluoride of phosphorus is 3.93 g/l at stp. calculate the molar...
the density of a gaseous fluoride of phosphorus is 3.93 g/l at stp. calculate the molar mass of the fluoride and determine its molecular formula
Calculate ΔS (for the system) when the state of 3.10 mol of perfect gas atoms, for...
Calculate ΔS (for the system) when the state of 3.10 mol of perfect gas atoms, for which Cp,m = 5/2 R, is changed from 25°C and 1.00 atm to 125°C and 5.00 atm. How do you rationalize the sign of ΔS? a. Though ΔS (system) is positive, the process can still occur spontaneously if ΔS (total) is negative. b. Though ΔS (total) is negative, the process can still occur spontaneously if ΔS (system) is positive. c. Though ΔS (system) is...
Use data in Appendix C in the textbook to calculate ΔH∘ in (kJ/mol) , ΔS∘ in...
Use data in Appendix C in the textbook to calculate ΔH∘ in (kJ/mol) , ΔS∘ in (j/mol-K) , and ΔG∘ in (kJ/mol) at 25 ∘C for each of the following reactions: 2P(g)+10HF(g)→2PF5(g)+5H2(g) Appendix C: P(g): dH:316.4; dG: 280.0; S:163.2 HF(g): dH: -268.61; dG: -270.70; S:173.51 PF5(g): dH:-1594.4; dG: -1520.7; S: 300.8 H2(g): dH:217.94; dG: 203.26; S: 114.60
For a reaction with ΔH∘=−24 kcal/mol and ΔS∘=0.07 kcalmol−1K−1, calculate the equilibrium constant at: (1.) 30...
For a reaction with ΔH∘=−24 kcal/mol and ΔS∘=0.07 kcalmol−1K−1, calculate the equilibrium constant at: (1.) 30 ∘C and (2.) 150 ∘C.
Calculate the change in pH that occurs when 0.00100 mol of gaseous HCl is added to...
Calculate the change in pH that occurs when 0.00100 mol of gaseous HCl is added to a buffer solution that is prepared by dissolving: A) 4.92g of sodium acetate (molar mass = 82.03g/mol) in 250 mL of 0.150 mol/L of acetic acid solution? B) 0.492g of sodium acetate (molar mass = 82.03g/mol) in 250 mL of 0.0150 mol/L of acetic acid solution? Assume no change in volume upon addition of either the sodium acetate or HCl. (Ka for acetic acid...
calculate the change in pH that occurs when 0.00100 mol of gaseous HCL is added to...
calculate the change in pH that occurs when 0.00100 mol of gaseous HCL is added to a buffer solution that is prepared by dissolving 4.92 g of sodium acetate in 250 ml of 0.150 mol L^-1 of acetic acid solution? Assume no change in volume upon addition of either sodium acetate of HCL (Ka=1.8x10^-5)
Calculate ΔS if 2.10 mol of liquid water is heated from 0.00 ∘C to 13.5 ∘C...
Calculate ΔS if 2.10 mol of liquid water is heated from 0.00 ∘C to 13.5 ∘C under constant pressure if CP,m=75.3J⋅K−1⋅mol−1. The answer the the problem above is 7.62 J/K The melting point of water at the pressure of interest is 0.00 ∘C, and the enthalpy of fusion is 6.010 kJ⋅mol−1. The boiling point is 100. ∘C, and the enthalpy of vaporization is 40.65 kJ⋅mol−1. Calculate ΔS for the transformation of the same amount of water H2O(s,0.00∘C) →H2O(g,100.∘C) Can you...
ADVERTISEMENT
ADVERTISEMENT
ADVERTISEMENT