tión enthalpies Consider the following unbalanced reaction: ? Al(s) +? Fe203 (s) ===> Al,03 (s) + 2 Fe(s), AHrxn=? Thermodynamic data at 298.15 K: AHf(Fe203) = -822.16 kļ/mol, AHf(Al203) = -1669.8 k/mol. %3D The specific heat capacity of copper (Cu)-0.376812 g K), assumed to be constant. The molar mass of aluminum and Al203 is 26.98153849 and 101.961276 g/mol, respectively. (1) Calculate AHrxn from the formation enthalpies. Is the rn exothermic or endothermic? Solution: -847.64 kJ. Exothermic. AHrxn = (-1669.8)-(-822.16)=-847.64 kJ per 2 mol of Al (2) Calculate the reaction enthalpy per gram of Al(s). Solution: -15.71 k/ gram of AI. (-(847.64 / 2) kJ/mol of Al)/ (26.98 g/mol of Al)-. -15.71 k/gram of Al. (3) Assume that only 20 % of the released energy can be used to heat a metal (the 80 % remaining is wasted energy). How many grams of Al (s) are needed to heat a copper (Cu) mass of 1 kg by 100 Celsius? Solution: 12 g of Al(s).

tión enthalpies Consider the following unbalanced reaction: ? Al(s) +? Fe203 (s) ===> Al,03 (s) + 2 Fe(s), AHrxn=? Thermodynamic data at 298.15 K: AHf(Fe203) = -822.16 kļ/mol, AHf(Al203) = -1669.8 k/mol. %3D The specific heat capacity of copper (Cu)-0.376812 g K), assumed to be constant. The molar mass of aluminum and Al203 is 26.98153849 and 101.961276 g/mol, respectively. (1) Calculate AHrxn from the formation enthalpies. Is the rn exothermic or endothermic? Solution: -847.64 kJ. Exothermic. AHrxn = (-1669.8)-(-822.16)=-847.64 kJ per 2 mol of Al (2) Calculate the reaction enthalpy per gram of Al(s). Solution: -15.71 k/ gram of AI. (-(847.64 / 2) kJ/mol of Al)/ (26.98 g/mol of Al)-. -15.71 k/gram of Al. (3) Assume that only 20 % of the released energy can be used to heat a metal (the 80 % remaining is wasted energy). How many grams of Al (s) are needed to heat a copper (Cu) mass of 1 kg by 100 Celsius? Solution: 12 g of Al(s).

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...

See similar textbooks

Similar questions

Calculate ΔH°25° for the reaction: Fe3O4(s)+2 C(s, graphite) = 3 Fe(s) + CO2(g) from the following data: 2 Fe(s)+3/2 O2(g) = Fe2O3(s) ΔH°25°c= -826 kJ Fe(s)+1/2 O2(g)= FeO(s) ΔH°25°c= -272 kJ FeO(s)+Fe2O3(s)= Fe3O4(s) ΔH°25°c= -1121 kJ C(s, graphite)+ CO2(g)= CO2(g) ΔH°25°c= -394 kJ
* 7. Skin imperfections and uneven discolorations are refined, resurfaced, and smoothed by crystals. Aluminum oxide is used by skin care specialists to alter the skin's surface. Scars, fine lines, wrinkles, and pigment changes brought on by sun exposure are a few examples. Calculate AS, AH°, and AG for following reactions using standard values of formation. What is their spontaneity? Are products or reactants favored? ENTHALPY (ΔΗ) ENTROPY (AS) GIBBS FREE (AG) SPONTANEITY: FAVORED: SUBSTANCES AB (J/mol K) AHK (kJ/mol 4Al(s) +30210) = 2Al2O36) Al(s) 28.3 0 0218) 205.0 0 AlzO3(s) 50.99 -1669.8
Unit Name: Thermodynamic Chemistry investigate and analyse energy changes and rates of reaction in physical and chemical processes, and solve related problems; Calculate the enthalpy of the following reaction:
Use the reaction for the formation of NH3 from its elements N2(g) and H2(g) . This reaction has the following thermodynamic data: ΔfHo (NH3) = - 45.9 kJ/mol and ΔfSo (NH3) = - 99.1 J/mol*K at 298 K a) Write a balanced equation (whole number ratios) for this process and write out the expression for the reaction quotient Q using partial pressures. b) Without doing any calculations, explain how the progression of the reaction will change (more reactants or more products) with respect to 1) increasing temperature, and 2) increasing pressure. c) Calculate the equilibrium constant K at 298 K d) Assuming that : ΔfHo is independent of temperature, calculate K at - 78o C
Can you help me figure this out?
Consider the following reaction under standard conditions, in which DHo and DSo are given. CO(g) + 2H2(g) --> CH3OH(g); DHo = -90.5 kJ, and DSo = -219.2 J/K What is DGo if the reaction is carried out at 250oC under standard conditions? Is the reaction spontaneous under this condition? (A) DGo = -35.7 kJ; the reaction is spontaneous (B) DGo = 145.3 kJ; the reaction is not spontaneous (C) DGo = -205.1 kJ; the reaction is spontaneous (D) DGo = 24.1 kJ; the reaction is not spontaneous
. Using the table provided, calculate the thermodynamic property of interest for each given reaction. Thermodynamic Data at 25 °C Species AH in kJ/mol AGº in kJ/mol So in J/(mol·K) Cu (s) 33.2 Cu (g) 337.4 297.7 166.4 CuO (s) -157.3 -129.7 42.6 H2 (g) 131.0 H2O (g) -241.8 -228.6 188.7 H2O (€) -285.8 -237.2 69.9 NO (g) 91.3 87.6 210.8 NO2 (g) 33.2 51.3 240.1 N2O4 (E) -19.5 97.5 209.2 N2O4 (g) 9.16 99.8 304.4 O2 (g) 205.0 ) Determine AS° for H2 (g) + ½ O2 (g) → H2O (g) at 25 °C. (ii) Determine AG° for 2 Cu (s) + O2 (g) → 2 CuO (s) at 25 °C. (iii) Determine AH° for H2O (8) → H2O (g) at 100 °C. (iv) Determine AG° for 2 NO2 (g) + N2O4 (g) at 100 °C.
Use Hess's Law to calculate the enthalpy change for the reaction AH=? from the following data: 2BaO(s) -(0 + (S) AH3-1107.0kJ AH=-822.5kJ (s)E00 ( 04 + (O + (s) %3D O-284.5 kJ O 538.0 kJ O 1391.5 kJ Previous
THERMODYNAMICS: Use the given standard enthalpies of formation to calculate the ΔHo (in kJ) for the hypothetical reaction: (Round off the final answer to ONE decimal place. Do not include the unit.) 2X2D (g) + 3M2 (g) → 2X2M (l) + 2DM2 (g) ΔHof for X2D (g) = -22.4 kJ/mol ΔHof for DM2 (g) = -290.7 kJ/mol ΔHof for X2M (l) = -288.3 kJ/mol ΔHof for M2 (g) = 0 kJ/mol show sol'n please.
Use the following information to calculate the standard free energy change (AG°) and equilibrium constant (K) for the following system: CaCO3(s) = CaO(s) + CO2(g) T= 900.0 °C AH;° values (kJ/mol): CaO(s) = -634.9, CO2(g) = -393.51, CaCO3(s) =–1220.0 %3D S° values (J/mol K): CaO(s) = 110.0, CO2(g) = 213.8, CACO3(s) = 38.1 %3D %3D %3D
Using the equation for photosynthesis below, answer the following equations 2800kJ + 6 CO: (g) + 6 HeO () > CeHi2Oe (s) + 6 02 (g)
For the reactionN2(g) + 3 H2(g) 2 NH3(g)G° = -30.4 kJ and S° = -198.7 J/K at 311 K and 1 atm.This reaction is (reactant, product)_______ favored under standard conditions at 311 K.The standard enthalpy change for the reaction of 1.80 moles of N2(g) at this temperature would be _____kJ.