The standard free energy of formation, AG: , of a substance isthe free energy change for the formation of one mole of thesubstance from the component elements in their standardstates. These values are applicable at 25°C and are found inthermodynamic tables.The value of AG; for a substance gives a measure of thethermodynamic stability with respect to the componentelements. Negative values for a formation reaction indicatethermodynamic stability of the product. In other words, thecompound formed does not spontaneously decompose backinto the component elements. Positive values for a formationreaction indicate thermodynamic instability of the product.Thus, the compound will spontaneously decompose, thoughthe rate may be slow.The sign of AG: can be used to predict the feasibility ofsynthesizing a substance from its component elements. Thestandard free energy change for a reaction, AG°, is a statefunction and can be calculated from the standard free energiesof formation as follows:ΔG Ση, AG; (products) -Ση ΔG; (reactants)where np and n, represent the stoichiometric coefficients inthe balanced chemical equation for the reactants and productsrespectively. When ethanol (CH3CH2OH) is combusted, such as when in a gasoline blend, the followingreaction occurs:2CH3CH2OH(1) + 602(g)—4CО2 (8) + 6H20(g)Based on the standard free energies of formation given in the table below, what is the standardfree energy change for this reaction?AGSubstancekJ/mol)CH3 CH2 OH(1) –174.9O2 (g)CO2 (g)-394.4H2O(g)-228.6Express your answer to one decimal place and include the appropriate units.

Given : We have to calculate the Gibbs free energy change for the given reaction.Calculations: Given reaction is :2CH3CH2OH(l) + 6O2(g) --> 4CO2(g) + 6H2O(g)∆G =∆Gproducts-∆Greactants∆G =4∆GCO2+ 6∆GH2O-6∆GO2-2∆GCH3CH2OH∆G =4 x (-394.4) + 6 x (-228.6) -0 - 2x (-174.9)∆G =-2599.4KJ/mol ~ 2.6 x 103KJ/mol

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2CH3CH2OH(1) + 602(g)—4CО2(в) + 6H20(g) Based on the standard free energies of formation given in the table below, what is the standard ree energy change for this reaction? AG Substance kJ/mol) |СHз CH2ОH(1)| — 174.9

2CH3CH2OH(1) + 602(g)—4CО2(в) + 6H20(g) Based on the standard free energies of formation given in the table below, what is the standard ree energy change for this reaction? AG Substance kJ/mol) |СHз CH2ОH(1)| — 174.9

Chemistry

10th Edition

ISBN:9781305957404

Author:Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCoste

Publisher:Steven S. Zumdahl, Susan A. Zumdahl, Donald J. DeCoste

Chapter1: Chemical Foundations

Section: Chapter Questions

Problem 1RQ: Define and explain the differences between the following terms. a. law and theory b. theory and...

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https://openstax.org/books/chemistry-atoms-first-2e/pages/g-standard-thermodynamic-properties-for-selected-substances a) Calculate ΔG° for the following reaction using the Standard Free Energy of Formation values. (SHOW CALCULATION) N2(g) + 3 F2(g) → 2 NF3(g) b) Is this reaction spontaneous or nonspontaneous?
For the reaction 4HCI(g) + O2(g)- →2H2O(g) + 2C1½(g) AH° = -114.4 kJ and AS° = -128.9 J/K The standard free energy change for the reaction of 1.62 moles of HCl(g) at 332 K, 1 atm would be kJ. This reaction is (reactant, product) favored under standard conditions at 332 K. Assume that AH° and AS° are independent of temperature.
a) b)
For the reaction 4HCI(g) + O2(9)– →2H20(g) + 2Cl,(g) AH° = -114.4 kJ and AS° = -128.9 J/K The standard free energy change for the reaction of 1.84 moles of HCI(g) at 296 K, 1 atm would be kJ. This reaction is (reactant, product) favored under standard conditions at 296 K. Assume that AH° and AS° are independent of temperature.
G.59.
Using the thermodynamic information in the ALEKS Data tab, calculate the standard reaction free energy of the following chemical reaction: P,010 (s) + 6H,0 (1) → 4H;PO4 (s) Round your answer to zero decimal places. kJ
A student determines the value of the equilibrium constant to be 6.29×104 for the following reaction.S(s,rhombic) + 2CO(g)SO2(g) + 2C(s,graphite)Based on this value of Keq:G° for this reaction is expected to be (greater, less) fill in the blank than zero.Calculate the free energy change for the reaction of 1.85 moles of S(s,rhombic) at standard conditions at 298K. G°rxn = _____ kJ
Use this information to complete the table below.
A student determines the value of the equilibrium constant to be 2.30 x 10¹6 for the following reaction. Ca(OH)2 (aq) + 2HCl(aq) → CaCl₂ (s) + 2H₂O(1) Based on this value of Keq AGO for this reaction is expected to be than zero. Calculate the free energy change for the reaction of 1.57 moles of Ca(OH)2 (aq) at standard conditions at 298 K. AGO rxn kJ
Calculate standard free energy change using AGf values. Consider the reaction 2NH3(g) + 3N₂O(g)4N₂(g) + 3H₂O(g) Use standard free energies of formation to calculate the standard free energy change for this reaction at 25°C. kJ/mol AG° = rxn
Calculate the free energy change under nonstandard state conditions. Use standard thermodynamic data (in the Chemistry References) to calculate triangleG at 298.15 K for the following reaction, assuming that all gases have a pressure of 10.35 mm Hg. 2S02(g) + O2(g) 2SO3(g) triangleG= kJ/mol Calculate the equilibrium constant from the standard free energy change. Using standard thermodynamic data (linked), calculate the equilibrium constant at 298.15 K for the following reaction. C2H4(g) + H2O(g)——->CH3CH2OH(g)