Q4

Identify the change in state that does NOT have an increase in entropy.   a water evaporating   b ice melting   c water freezing   d water boiling   e dry ice subliming

which statement about entropy is true? non-spontaneous reactions sometimes will happen all by themselves entropy stops when pure substances are in solid state the entropy of the universe is increasing during a change of state there is no change in entropy

For each of the processes, determine whether the entropy of the system is increasing or decreasing. The system is underlined. Entropy is increasing Entropy is decreasing Answer Bank a document goes through a paper shredder iron rusts to iron oxide a block of dry ice sublimates to CO, gas water vapor from the air forms water droplets on the outside of a cold soft drink can a slice of hot pizza cools off on a plate

Methanogenic bacteria convert acetic acid (CH3COOH) to CO2(g) and CH4(g).   ΔH°f, (kJ/mol) ΔG°f, (kJ/mol) CH3COOH -484.5 -389.9 CO2(g)  -393.5    -394.4 CH4(g)  -74.8  -50.8 Calculate ΔH°rxn. ΔH°rxn = ____ kJ Calculate ΔG°rxn. ΔG°rxn = ___kJ

What is AS for the combustion of propane? C3H8(g) +502(g) → 3CO2(g) + 4H₂O(g) Substance C3H8(g) O2(g) CO2(g) H₂O(g) S(J/K mol) 269.9 205.0 213.6 188.7

TRUE OR FALSE 1. Lowering the temperature of the system will lead to an increase in entropy. 2. Spontaneous process occurs from an ordered state to a more random arrangement. 3. The increase in the number of particles can lead to an increase in entropy. 4. A negative ΔS indicates an increase in randomness of a system 5. Lowering the temperature of the system will lead to a decrease in entropy. 6. The second law of thermodynamics states that the total entropy of a system decreases in any spontaneous process. 7. Free energy is a portion of the total energy of a system that is available to do useful work. 8. If change of G is positive, then it's non-spontaneous. 9. Spontaneity can predict the rate of a process (i.e., how fast or slow it occurs). 10. The increase in the number of particles can lead to a decrease in entropy.

When the temperature-time data graph was reviewed, it was found that an error had been made in determining ΔT. Instead of 4.76 °C, ΔT was actually 4.70 °C. Based on this change only, calculate the correct ΔH neutralization for the reaction of NH3, and acetic acid.

Consider the following reaction: H2 + Br2  →. HBr ΔH = -43 kcal/mol ΔS = 0.0272 kcal/mol   What is the ΔG value for the reaction at 300 K?

All the following involve an increase in entropy except   most endothermic reactions   sublimation   vaporization   combustion

Short answers please

Read the descriptions of physical or chemical changes in the table below. Then decide whether the change will be spontaneous, if you can. Change A solid absorbs heat and turns to a gas. During an exothermic chemical reaction, a solid is consumed and a gas produced. Is this change spontaneous? Yes. No. Can't decide with information given. ○ Yes. ○ No. Can't decide with information given. An endothermic chemical reaction between two liquids results in gaseous products. Yes. No. ○ Can't decide with information given.

Read the descriptions of physical or chemical changes in the table below. Then decide whether the change will be spontaneous, if you can. Change During an endothermic chemical reaction, four moles of gaseous reactants are turned into two moles of gaseous products. A solid precipitates from a solution, releasing heat as it does so. A solid absorbs heat and turns to a gas. Is this change spontaneous? Yes. O No. O Can't decide with information given. O Yes. O No. O Can't decide with information given. O Yes. O No. O Can't decide with information given.

Please don't provide handwriting solution

5. The change in enthalpy for a certain reaction is a small, positive number. The change in entropy for this reaction is an extremely large positive number. Is this reaction exergonic or endergonic?exergonic  endogonic

Now calculate the change in entropy (delta S) for the following reaction, using the thermodynamic tables (from your book or on Moodle).    P4 (g)  +   10 Cl2 (g)   →    4 PCl5 (g)   Select one: a. 3922 J/K b. – 113 J/K c. 1412 J/K d. 856 J/K e. – 856 J/K f. – 1098 J/K g. – 1.50 x 10^2 J/K h. none of these i. 2510 J/K

In which is there a positive entropy change? A. Magnesium combusts in air to form Magnesium oxide B. Condensation of steam C. Dry ice sublimates D. Nitrogen and hydrogen pas reacts to form gaseous ammonia

A student determines the value of the equilibrium constant to be 4.54x10-15 for the following reaction. 2CO₂(g) + 5H₂(g)→→→→→C₂H₂(g) + 4H₂O(g) Based on this value of Keq: AGᵒ for this reaction is expected to be (greater, less) Calculate the free energy change for the reaction of 1.76 moles of CO₂(g) at standard conditions at 298K. kJ AGOrxn than zero.

Predict whether the entropy change is greater or less than zero for the following process: dry ice subliming O change in entropy 0 change in entropy 0

How many of the following processes are accompanied by a positive entropy change? heating a pot of water spilling a glass of milk dissolving sugar in water making ice cubes melting an icicle Group of answer choices 1 2 4 3 5

Consider the reaction: CaCO3(s) ↔ CaO(s) + CO2(g) The reaction enthalpy and entropy are: ΔHo rx = -117.1 kJ∙mol-1; ΔSo rx = -362 J∙K-1mol-1. Assume that these values are independent of temperature.   If this reaction is in equilibrium and the temperature is increased, what do you expect will happen? Write one of the following: net reaction to right, net reaction to left, no net reaction and explain your reasoning. Do not use Le Chatelier’s Principle

32) Which reaction is accompanied by an increase in entropy? A) C8H16() + 12 O₂(g) → 8 CO₂(g) + 8 H₂O(1) B) Ba(OH)₂ (s) + CO₂(g) → BaCO3(s) + H₂O(l) C) NH4NO₂ (s)→→ N₂(g) + 2 H₂O(1) D) 2 C₂H₂(g) + 5 O₂(g) → 4 CO₂(g) + 2 H₂O(s) E) N₂(g) + 3 H₂(g) → 2 NH3(g) mion sonste

Read the descriptions of physical or chemical changes in the table below. Then decide whether the change will be spontaneous, if you can. Change Is this change spontaneous? ○ Yes. A chemical reaction between two liquids creates gaseous products. ○ No. Can't decide with information given. During an endothermic chemical reaction, a gas is consumed and a liquid produced. Yes. ○ No. Can't decide with information given. During an exothermic chemical reaction, four moles of gaseous reactants are turned into two moles of gaseous products. Yes. No. Can't decide with information given.

Chp 19 #28 & # 30

For each of the processes, determine whether the entropy of the system is increasing or decreasing. The system is underlined. Entropy is increasi iron rusts to iron oxide a block of dry ice sublimates to CO₂ gas a glass bowl falls and shatters Answer Bank Entropy is decreasing a water bottle cools down in a refrigerator dissolved sugar precipitates out of water to form rock candy

MISSED THIS? Read Section 19.8 (Pages 871 - 877); Watch IWE 19.6. Liquid methanol burns in oxygen to form gaseous carbon dioxide and gaseous water. Substance H° (kJ/mol) S° (J/(mol. K)) CH3OH (1) -238.6 126.8 O2 (g) 0 CO₂ (g) -393.5 CO2(aq) -413.8 H₂O(g) -241.8 H₂O(1) -187.8 205.2 213.8 117.6 188.8 70.0 stan 1 Periodic Liquid methanol (CH3OH(1)) burns in oxygen (O₂ (g)) to form gaseous carbon dioxide (CO2 (g)) and gaseous water (H₂O(g)), which is represented by the following balanced equation: 2CH3OH(1) +302(g) → 2CO2 (g) + 4H₂O(g) The balanced chemical equation is neeed to calculate the standard enthalpy change for a reaction (AH) the standard entropy change for a reaction (AS) from the standard enthalpies of formation and standard molar entropies, respectively. Part B Calculate AHxn at 25 °C. Express your answer in kilojoules to three significant figures. AH = VE ΑΣΦ C ? kJ

Given that the reaction of 4 NH3 (g) + 5 O2 (g) → 4 NO (g) + 3 H20 (g) ΔΗ - - 906 kJ What would AH for NO (g) + ? H20 (g) → NH3 (g) + O2 (g) be? 2. 906 kJ 226.5 kJ -226.5kJ 453 kJ