Chapter 16 Quiz Entropy and Free Energy

Consider the combustion of ethane: 2C2H6 + 7O2 --> 4CO2 + 6H2O Substance ΔHf C2H6 -84.7 O2 0 CO2 -393.5 H2O -242.0 What is ΔHcombustion (ΔHreaction) ?   Question 2 options:   550.8 kJ   -2856.6 kJ   2856.6 kJ   -550.8 kJ

#5 Be sure to answer all parts. Determine Δngas for each of the following reactions: (a) MgCO3(s)→MgO(s) + CO2(g) =____mol (b) 2 H2(g) + O2(g)→2 H2O(l) =____mol (c) HNO3(l) + ClF(g)→ClONO2(g) + HF(g) =____mol

Calculate ΔHf0 of HPO3 given the data below                    P4O10  +  4 HNO3   ---->  4 HPO3   +  2 N2O5    ΔHorxn = -180.6 kJ             ΔHf0  (kJ/mol)     -2984        -174.1                x             -43.1        a) -528.0 kJ/mol          b) -1471 kJ/mol      c) –943.7 kJ/mol      d) 1471 kJ/mol    e) -954.5 kJ/mol

What is the boiling point water at the top of Mt Everest (atmospheric pressure = 0.54 atm)? H2O(l)↽−−⇀H2O(g) Thermodynamic Table at 25 ∘C25 ∘C Substance Δ?∘f (kJ/mol) S∘ (J/mol‑K) Δ?∘f(kJ/mol) H2O(l)H2O(l) −285.8 70.0 −237.1 H2O(g)H2O(g) −241.8 188.8 −228.6

Arrange the following reactions in order of increasing ΔrxnS and briefly explain your reasoning. a) S(s)+O2(g)⟶SO2(g) b) H2(g)+O2(g)⟶H2O2(ℓ) c) CO(g)+3H2(g)⟶CH4(g)+H2O(ℓ) d) C(s)+H2O(g)⟶CO(g)+H2(g)

Need help with only d,e and f

Arrange the following reactions in order of increasing ΔrxnS and briefly explain your reasoning. a) S(s) + O2(g) ⟶ SO2(g)b) H2(g) + O2(g) ⟶ H2O2(ℓ)c) CO(g) + 3 H2(g) ⟶ CH4(g) + H2O(ℓ)d) C(s) + H2O(g) ⟶ CO(g) + H2(g)

Please show steps and explain why the answer is not -4.10J/K. Thanks.

18. Calculate the AH of reaction for CIF(g)F2(g)> CIF3(g) given the following data: 1) 2CIF(g)O2(g) -> Cl20(g) +F20(g) ΔΗ -167.4 kJ 2) 2CIF3(g)202(g)Cl20(g) +3 F2O(g) ΔΗ-341.4 kJ 3) 2F2(g)O2(g)->2F20(g) AH -43.4 kJ a. -217 kJ b. 465 kJ c. -174 kJ d. 233 kJ е. -109 kJ

5:50 For the reaction Question 13 of 15 2 H₂(g) + O₂(g) → 2 H₂O(g) Substance H₂ (g) O₂ (g) H₂O (g) which equation would be used to determine the entropy change? A) (2A + B) - 2C B) C- (A + B) C) 2C - (2A + B) D) 2A + B + 2C E) 2C - (A + B) Sº A B C ..5G Tap here or pull up for additional resources Submit

1:44 1 LTE 4 1 Search Question 20.b of 23 Show Answer Consider the reaction Cl2(g) + Br2(g) → 2 BrCI(g) at 25 °C. Which of the following best explains why the change in entropy is so small? A) All of the components in the chemical equation are gases. B) There are the same moles of gas on both sides of the reaction. C) The temperature of the reaction does not change. Tap here or pull up for additional resources

Given the values of AH and AS, which of the following changes will be spontaneous at constant T and P? (Select all that apply.) O AH = +25 kJ, AS = +8.0 J/K, T= 300. K O AH = +23 kJ, AS =+100. J/K, T= 300. K O AH=-10. kJ, AS = +8.0 J/K, T= 295 K AH=-10. kJ, AS = 40. JK, T= 100. K O None of the above.

For a spontaneous chemical reaction which of the following are possible signs of ΔΔH and ΔΔS? Select one: a. both b and c b. ΔΔH = (+) and ΔΔS = (-) c. ΔΔH = (-) and ΔΔS = (+) d. neither b nor c Clear my choice

d)The ΔH°f of Ar(g) is   1.positive. 2.negative. 3.zero. 4.must be determined experimentally.   e)The reaction K + Cl2 + 2O2→ KClO4 has a ΔH = -432 kJ/mol. What is the ΔH of:    2KClO4 → 2K + Cl2 + 4O2?   1.-432 kJ/mol 2.+432 kJ/mol 3.-216 kJ/mol 4.+864 kJ/mol   f)Which of the following is a formation reaction?   1.K+(g) + Br-(g) → KBr(s) 2.2K(s) + Br2(g) → 2KBr(s) 3.K(g) + Br(g) → KBr(s) 4.none of the above

Please correct answer and step by step solution

Hi,  Help with i-k part.   The process of melting solid ice to produce water has the following thermodynamic values:  Δ H = + 1.44 k c a l / m o l a n d Δ S = + 5.26 c a l / m o l ⋅ K. a) What is the value for Δ G at 263K in cal/mol?b) Is melting ice spontaneous at 263K?c) What about the reverse reaction? Would liquid water spontaneously freeze at 263K?d) Convert 263K to ∘ C. Would you expect ice to melt at this temperature?e) What is the value for Δ G at 283K in cal/mol?f) Is melting ice spontaneous at 283K?g) What about the reverse reaction? Would liquid water spontaneously freeze at 283K?h) Convert 283K to ∘ C. Would you expect ice to melt at this temperature?i) What is the value for Δ G at 273K in cal/mol? (Be careful to only use 3 Sig Figs in your calculations)j) Convert 273K to ∘ C. Would you expect ice to melt at this temperature?k) A Δ G of 0 indicates a system is at equilibrium. Use this to explain which process is spontaneous at 273K, melting or freezing?

10

Which of the following conditions describe a reaction that is spontaneous at "low" temperature and nonspontaneous at "high" temperature? Group of answer choices: A) ΔH (-),  ΔS (+) B) ΔH (+),  ΔS (-) C) ΔH (+),  ΔS (+) D) ΔH (-),  ΔS (-) E) None are true.