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Spontaneous Reaction Solutions Library

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162 solutions

Spontaneous Reaction

Q. Classify the possible combinations of signs for a reaction's Δ H and Δ S values by the resulting spontaneity. ΔH = -                     ΔH = +    ...

Solved • Apr 30, 2020

Spontaneous Reaction

Q. Complete the following table on reaction spontaneity.

Solved • Apr 21, 2020

Spontaneous Reaction

Q. Which of the following reactions would you predict to be spontaneous at all temperatures (assuming ΔH°­rxn does not change significantly with tempe...

Solved • Apr 13, 2020

Spontaneous Reaction

Q. In thermochemistry, a "coupled reaction" is based on the concept that:a. the enthalpy and entropy of a reaction are interdependent ("coupled") on e...

Solved • Mar 31, 2020

Spontaneous Reaction

Q. Which of the following processes are spontaneous, and which are nonspontaneous: a) the ripening of a banana, b) dissolution of sugar in a cup of ho...

Solved • Mar 23, 2020

Spontaneous Reaction

Q. Classify each process as spontaneous or nonspontaneous.Water is separated into H2 and O2 gas at 25 °C.A cup of hot coffee cools to room temperature...

Solved • Mar 18, 2020

Spontaneous Reaction

Q. Predict the sign of ΔS° for each of the following reactions. In addition, given the ΔH° values provided, predict at what temperatures (if any) the ...

Solved • Mar 16, 2020

Spontaneous Reaction

Q. Predict the sign of ΔS° for each of the following reactions. In addition, given the ΔH° values provided, predict at what temperatures (if any) the ...

Solved • Mar 16, 2020

Spontaneous Reaction

Q. Predict the sign of ΔS° for each of the following reactions. In addition, given the ΔH° values provided, predict at what temperatures (if any) the ...

Solved • Mar 16, 2020

Spontaneous Reaction

Q. Determine whether each of these processes is reversible or irreversible.Drag the appropriate items to their respective bins.Bins: Reversible and Ir...

Solved • Mar 13, 2020

Spontaneous Reaction

Q. Which of the following is always true for a spontaneous process?A) ∆H > 0B) ∆G > 0C) ∆G < 0D) ∆S < 0

Solved • Feb 18, 2020

Spontaneous Reaction

Q. A certain process has ∆H° < 0, ∆S° > 0, and ∆G° < 0. The values of ∆H° and ∆S° do not depend on the temperature. Which of the following is...

Solved • Feb 18, 2020

Spontaneous Reaction

Q. For the reactionC2H6 (g) → C2H4 (g) + H2 (g) ΔH° is +137 kJ/mol and ΔS° is +120 J/K • mol. This reaction is ________.A) spontaneous at all temperat...

Solved • Jan 28, 2020

Spontaneous Reaction

Q. Find the temperature above which a reaction with a ΔH of 123.0 kJ/mol and as ΔS of 90.00 J/K•mol becomes spontaneous.

Solved • Jan 28, 2020

Spontaneous Reaction

Q. A reaction for which ΔH° and ΔS° are both negative, is a. Nonspontaneous at low temperatures and spontaneous at high temperaturesb. Nonspontaneous ...

Solved • Dec 19, 2019

Spontaneous Reaction

Q. Potassium nitrate dissolves spontaneously in water, and this process is endothermic. Indicate whether each of the thermodynamic parameters below is...

Solved • Dec 19, 2019

Spontaneous Reaction

Q. The signs of ΔG, ΔH, and ΔS at 25°C are shown below for three reactions.Reaction      ΔG      ΔH      ΔSI                    –         +         +I...

Solved • Dec 18, 2019

Spontaneous Reaction

Q. A reaction for which ΔH° is positive and ΔS° is negative, isa. Nonspontaneous only at low temperaturesb. Spontaneous only at high temperaturesc. No...

Solved • Dec 17, 2019

Spontaneous Reaction

Q. The exothermic reaction 2NO2(g) <=> N2O4(g), is spontaneous...a. cannot be determinedb. the reaction is nonspontaneous at all temperaturesc. ...

Solved • Dec 16, 2019

Spontaneous Reaction

Q. For the reaction, Fe2O3 (s) + 3 H2(g) <=> 2 Fe(s) + 3 H2O(g), ΔG° = 53 kJ at 25 °C and  ΔH° = 100 kJ.  Which of the following is completely t...

Solved • Dec 16, 2019

Spontaneous Reaction

Q. For the following reaction, ΔH rxn = −120 kJ / mol-rxn and ΔS rxn = −150 J / mol-rxn•K:2NO(g) + O2(g) → 2NO2(g)At what temperatures will this react...

Solved • Aug 25, 2019

Spontaneous Reaction

Q. ΔG° = ΔH° - T ΔS°For the reaction Cu2O(s) + C(s) → 2Cu(s) + CO(g)a. would you expect a positive or negative change in entropy? Explain your answer....

Solved • Aug 7, 2019

Spontaneous Reaction

Q. Consider what happens when a sample of the explosive TNT is detonated under atmospheric pressure.Is the detonation a reversible process?

Solved • Jan 3, 2019

Spontaneous Reaction

Q. At what temperatures is the following reaction, the reduction of magnetite by graphite to elemental iron, spontaneous? Fe3O4(s)+2C(s,graphite) ...

Solved • Jan 3, 2019

Spontaneous Reaction

Q. As shown here, one type of computer keyboard cleaner contains liquefied 1,1-difluoroethane (C2H4F2), which is a gas at atmospheric pressure. When t...

Solved • Jan 3, 2019

Spontaneous Reaction

Q. Indicate whether each of the following statements is true or false.The reaction of Na(s) with Cl2 (g) to form NaCl(s) is a spontaneous process.

Solved • Jan 3, 2019

Spontaneous Reaction

Q. For each of the following processes, indicate whether the signs of S and H are expected to be positive, negative, or about zero.A diatomic molecule...

Solved • Jan 3, 2019

Spontaneous Reaction

Q. Two different gases occupy two separate bulbs. Consider the process that occurs when the stopcock separating the gases is opened, assuming the gase...

Solved • Jan 3, 2019

Spontaneous Reaction

Q. Two different gases occupy two separate bulbs. Consider the process that occurs when the stopcock separating the gases is opened, assuming the gase...

Solved • Jan 3, 2019

Spontaneous Reaction

Q. Two different gases occupy two separate bulbs. Consider the process that occurs when the stopcock separating the gases is opened, assuming the gase...

Solved • Jan 3, 2019

Spontaneous Reaction

Q. Suppose you have a system made up of water only, with the container and everything beyond being the surroundings. Consider a process in which the w...

Solved • Jan 3, 2019

Spontaneous Reaction

Q. Consider the vaporization of liquid water to steam at a pressure of 1 atm.In what temperature range is it a nonspontaneous process?

Solved • Jan 3, 2019

Spontaneous Reaction

Q. Consider a system consisting of an ice cube.Under what conditions can the ice cube melt reversibly?

Solved • Jan 3, 2019

Spontaneous Reaction

Q. A reaction is spontaneous under a certain set of conditions. Select all equations that must be true for this reaction under these conditions: ΔGrxn...

Solved • Jan 3, 2019

Spontaneous Reaction

Q. Consider the following reaction: C2H4(g) + H2(g) → C2H6(g), ΔH = –137.5 kJ, ΔS = –120.5 J/KDoes ΔG become more negative or more positive as the tem...

Solved • Jan 3, 2019

Spontaneous Reaction

Q. Without doing any calculations, determine the sign of ΔSsys and ΔSsurr for each of the chemical reactions below. In addition, predict under what te...

Solved • Jan 3, 2019

Spontaneous Reaction

Q. Consider the signs for ΔHrxn and ΔSrxn for several different reactions. In which case is the reaction spontaneous at all temperatures?a) ΔHrxn <...

Solved • Jan 3, 2019

Spontaneous Reaction

Q. Consider the following reaction occurring at 298 K: N2O(g) + NO2(g) ⇌ 3 NO(g)What temperature is required to make the reaction spontaneous under st...

Solved • Jan 3, 2019

Spontaneous Reaction

Q. Our atmosphere is composed primarily of nitrogen and oxygen, which coexist at 25 ˚C without reacting to any significant extent. However, the two ga...

Solved • Jan 3, 2019

Spontaneous Reaction

Q. Fill in the blanks in the table below where both ΔH and ΔS refer to the system.

Solved • Jan 3, 2019

Spontaneous Reaction

Q. Which of the following processes are spontaneous?The extraction of iron metal from iron ore.

Solved • Jan 3, 2019

Spontaneous Reaction

Q. Which of the following processes are spontaneous?Drawing heat energy from the oceans surface to power a ship.

Solved • Jan 3, 2019

Spontaneous Reaction

Q. Which of the following processes are nonspontaneous? Are the nonspontaneous processes impossible?a. a bike going up a hillb. a meteor falling to Ea...

Solved • Jan 3, 2019

Spontaneous Reaction

Q. The Ostwald process for the commercial production of nitric acid involves three steps:c. Is there a thermodynamic reason for the high temperature i...

Solved • Dec 3, 2018

Spontaneous Reaction

Q. Consider two reactions for the production of ethanol:C2H4 (g) + H2O (g) → CH3CH2OH (l)C2H6 (g) + H2O (g) → CH3CH2OH (l) + H2 (g)Which would be the ...

Solved • Nov 30, 2018

Spontaneous Reaction

Q. The major industrial use of hydrogen is in the production of ammonia by the Haber process:3H2 (g) + N2 (g) → 2NH3 (g)a. Using data from Appendix 4,...

Solved • Nov 30, 2018

Spontaneous Reaction

Q. Hydrogen cyanide is produced industrially by the following exothermic reaction:Is the high temperature needed for thermodynamic or kinetic reasons?

Solved • Nov 30, 2018

Spontaneous Reaction

Q. At what temperatures will the following processes be spontaneous?d. ΔH = -18 kJ and ΔS = +60. J/K

Solved • Nov 30, 2018

Spontaneous Reaction

Q. At what temperatures will the following processes be spontaneous?b. ΔH = +18 kJ and ΔS = +60. J/K

Solved • Nov 30, 2018

Spontaneous Reaction

Q. At what temperatures will the following processes be spontaneous?a. ΔH = -18 kJ and ΔS = -60. J/K

Solved • Nov 30, 2018

Spontaneous Reaction

Q. When ammonium chloride is added to water and stirred, it dissolves spontaneously and the resulting solution feels cold. Without doing any calculati...

Solved • Nov 29, 2018

Spontaneous Reaction

Q. Consider the decomposition of red mercury(II) oxide under standard state condition.2HgO(s, red) ⟶ 2Hg(l) + O 2(g)(b) Above what temperature does th...

Solved • Nov 29, 2018

Spontaneous Reaction

Q. Among the many complex ions of cobalt are the following:Co(NH3)63+(aq) + 3en(aq) ⇌ Co(en)33+(aq) + 6NH3(aq)where “en” stands for ethylenediamine, H...

Solved • Nov 26, 2018

Spontaneous Reaction

Q. A helium-filled balloon spontaneously deflates overnight as He atoms diffuse through the wall of the balloon. Describe the redistribution of matter...

Solved • Nov 26, 2018

Spontaneous Reaction

Q. Indicate whether the following process is spontaneous or nonspontaneous:A raindrop falling to the ground

Solved • Nov 26, 2018

Spontaneous Reaction

Q. A reaction that occur in the internal combustion engine isN2(g) + O2(g) ⥫⥬ 2NO(g)ΔH° = 180.6 kJ/mol; ΔS° = 24.8 J/mol KAt what temperature (in K) d...

Solved • Nov 26, 2018

Spontaneous Reaction

Q. Consider the combustion of butane gas:C4H10(g) + 13/2 O2(g) ⟶ 4CO2(g) + 5H2O(g)(a) Predict the signs of ΔS° and ΔH°. Explain.

Solved • Nov 26, 2018

Spontaneous Reaction

Q. Which of these processes are spontaneous? (a) A satellite falls to Earth. (b) Water decomposes to H2 and O2 at 298 K and 1 atm. (c) Average car pri...

Solved • Nov 21, 2018

Spontaneous Reaction

Q. Which of these statements are true? 

Solved • Jun 19, 2018

Spontaneous Reaction

Q. If ΔH = -80.0 kJ and ΔS = -0.400 kJ/K, the reaction is spontaneous below a certain temperature. Calculate that temperature. Express your answer num...

Solved • Jun 16, 2018

Spontaneous Reaction

Q. Making Methanol The element hydrogen is not abundant in nature, but it is a useful reagent in, for example, the potential synthesis of the liquid f...

Solved • May 4, 2018

Spontaneous Reaction

Q. The following generic reaction will always be spontaneous if the change in enthalpy is________ and the change in entropy is _________. negative, ne...

Solved • May 3, 2018

Spontaneous Reaction

Q. For a particular reaction, delta Hº is 55.4 kJ/mol and delta Sº is 94.1 J/(molK). Assuming these values change very little with temperature, over w...

Solved • Apr 2, 2018

Spontaneous Reaction

Q. Which of the following processes are spontaneous? Select all that apply. a. a satellite falling to Earthb. water decomposing to H2 and O2 at 298 K ...

Solved • Mar 30, 2018

Spontaneous Reaction

Q. Which of the following processes are spontaneous?a. Earth moving around the Sunb. A boulder rolling up a hillc. Sodium metal and chlorine gas react...

Solved • Mar 30, 2018

Spontaneous Reaction

Q. Which statement is true regarding the sublimation of dry ice (solid CO2)?a. ΔH is positive, ΔS is negative, and ΔG is positive at all temperatures....

Solved • Mar 26, 2018

Spontaneous Reaction

Q. Above what temperature does the following reaction become nonspontaneous?2 H2S(g) + 3 O2(g) → 2 SO2(g) + 2 H2O(g)H= -1036 kJ; S= -153.2 J/K 

Solved • Mar 23, 2018

Spontaneous Reaction

Q. Above what temperature does the following reaction become non-spontaneous?H2S + 3O2 → 2SO2 + 2H2OΔH= -1036 kJΔS= -153.2 J/K

Solved • Mar 22, 2018

Spontaneous Reaction

Q.  Consider a reaction that has a positive ΔH and positive ΔS. Which of the following statements is TRUE?a. the reaction will be spontaneous at high ...

Solved • Mar 22, 2018

Spontaneous Reaction

Q. Above what temperature does the following reaction become nonspontaneous?FeO(s) + CO(g) → CO2 (g) + Fe(s)ΔH = -11.0 kJ; ΔS = -17.4 J/K  

Solved • Mar 22, 2018

Spontaneous Reaction

Q. For the decomposition of calcium carbonate, consider the following thermodynamic data.ΔH∘rxn =178.5kJ/mol, ΔS∘rxn = 161.0J/(mol⋅K)Calculate the tem...

Solved • Mar 21, 2018

Spontaneous Reaction

Q. Consider the following reaction at 120°C. Which statement must be true?H2O(l) → H2O(g)a. The reaction is not spontaneous.b. The reaction is spontan...

Solved • Mar 20, 2018

Spontaneous Reaction

Q. At constant pressure, the following reaction is exothermic. The reaction (as written) is2NO2(g) → N2O4(g)a. spontaneous at all temperatures.b. spon...

Solved • Mar 20, 2018

Spontaneous Reaction

Q. For a particular reaction, ΔH°sys = 40 kJ and ΔS°sys = 50 J/K. Under what temperature parameters is the reaction spontaneous?a. When T < 10 K.b....

Solved • Mar 20, 2018

Spontaneous Reaction

Q. A particular chemical reaction has a negative ΔH and a negative ΔS. Which statement is correct?(A) The reaction is spontaneous at all temperatures....

Solved • Feb 26, 2018

Spontaneous Reaction

Q. Which of the following reactions are spontaneous (favorable)? 

Solved • Feb 22, 2018

Spontaneous Reaction

Q. Which of the following reactions are spontaneous (favorable)?a) Reaction Fb) Reaction Ec) Reaction Dd) Reaction Ce) Reaction Bf) Reaction A

Solved • Feb 22, 2018

Spontaneous Reaction

Q. If a solute dissolves in an endothermic process a) H bonds must exist between solvent and solute. b) strong ion-dipole forces must exist in the s...

Solved • Feb 15, 2018

Spontaneous Reaction

Q. Under standard conditions (298 K and 1 atm), which statement is true?i) diamond converts to graphite spontaneouslyii) graphite converts to diamond ...

Solved • Feb 12, 2018

Spontaneous Reaction

Q. What can be said about an exothermic reaction with a negative entropy change?The reaction isa) spontaneous at all temperatures.b) spontaneous at hi...

Solved • Dec 19, 2017

Spontaneous Reaction

Q. What can be said about an Endothermic reaction with a negative entropy change?The reaction isa. spontaneous at all temperatures.b. spontaneous at h...

Solved • Dec 19, 2017

Spontaneous Reaction

Q. Classify the following phase changes by the signs of the system's ΔH and ΔS.solid to liquid                gas to solidliquid to gas               ...

Solved • Dec 15, 2017

Spontaneous Reaction

Q. For a chemical reaction to be spontaneous for standard conditions which of the following must be true?a) ΔH°rxn > 0b) ΔS°rxn > 0c) ΔG°rxn &gt...

Solved • Oct 31, 2017

Spontaneous Reaction

Q. Which statement best describes the following endothermic reaction? C2H6(g) → C2H4(g) + H2(g) This reaction is ________. a. spontaneous at all te...

Solved • Oct 17, 2017

Spontaneous Reaction

Q. Consider the reaction: FeO(s) + Fe(s) + O2(g)→ Fe2O3(s) Given the following table of thermodynamic data, determine the temperature (in C°) which ...

Solved • Oct 17, 2017

Spontaneous Reaction

Q. A reaction that is spontaneous as written _________. a. is very rapid b. will proceed without outside intervention c. is also spontaneous in the...

Solved • Oct 17, 2017

Spontaneous Reaction

Q. For each phase change, determine the sign of ΔH and ΔS.Sublimation ,Freezing, Condensation, Deposition, Boiling , Melting a)   +ΔH,+ΔSb) -ΔH, -ΔSc)...

Solved • Sep 25, 2017

Spontaneous Reaction

Q. What can be said about an endothermic reaction with a negative entropy change?The reaction is

Solved • Sep 23, 2017

Spontaneous Reaction

Q. Which of the following statements best describes an endothermic reaction?a) The reaction must be spontaneous at all temperaturesb) The reaction may...

Solved • Aug 8, 2017

Spontaneous Reaction

Q. Sodium carbonate can be made by heating sodium bicarbonate:2 NaHCO3 (s) → Na2CO3(s) + CO2(g) + H2O(g)Given that standard enthalpy of reaction is 12...

Solved • Aug 8, 2017

Spontaneous Reaction

Q. Solid ammonium nitrate is very soluble in water. When it dissolves, the solution becomes very cold. Based on this information alone, what are the m...

Solved • Aug 8, 2017

Spontaneous Reaction

Q. For the reaction 2 C(s) + 2 H2(g) → C2H4(g)  ∆H°r = +52.3 kJ · mol−1 and ∆S°r =−53.07 J · K−1· mol−1 at 298 K. This reaction will be spontaneous ...

Solved • Jun 22, 2017

Spontaneous Reaction

Q. What would be the signs of ∆H and ∆S for the reaction AB4(g) → AB3(g) + B(g) ? 1. Both zero. 2. ∆H = +, ∆S = − 3. Impossible to tell from the i...

Solved • Jun 22, 2017

Spontaneous Reaction

Q. For the reaction 2 SO3(g) → 2 SO2(g) + O2(g) ∆H◦r = +198 kJ·mol−1 at 298 K. Which statement is true for this reaction? 1. The reaction will not ...

Solved • Jun 22, 2017

Spontaneous Reaction

Q. Ethane is C2H6. Consider the reaction below:  C2H6(g) ⇋ 2 Cgraphite(s) + 3 H2(g)  ∆G◦rxn = 7.86 kJ · mol−1 The decomposition of ethane is (sponta...

Solved • Jun 22, 2017

Spontaneous Reaction

Q. For the reaction 2 SO3(g) → 2 SO2(g) + O2(g) ∆H◦r = +198 kJ · mol−1 and ∆S◦r = 190 J · K−1 · mol−1 at 298 K. The forward reaction will be spontan...

Solved • Jun 22, 2017

Spontaneous Reaction

Q. Based on your knowledge of carbon allotropes, You can say that ∆G◦f of graphite is ________ and ∆G◦rxn of diamond → graphite is _______. 1. zero, ...

Solved • Jun 21, 2017

Spontaneous Reaction

Q. You observe that carbon dioxide sublimes. Which of the following statements about the signs of this process is/are true? I) Work (w) is positive. ...

Solved • Jun 21, 2017

Spontaneous Reaction

Q. Consider the following sets. Which one indicates a  NON-spontaneous reaction.A. ΔH° = -35 kJ; ΔS° = 40 J/K; and the temperature is 80°C.B. ΔH° = -1...

Solved • Apr 25, 2017

Spontaneous Reaction

Q. For the reaction A2(g) + B(s) → A2B(g)ΔH° > 0 and ΔS° > 0Which of the following statements is true?A. The reaction is spontaneous at low temp...

Solved • Apr 25, 2017