Ch.6 - Thermochemistry See all chapters
All Chapters
Ch.1 - Intro to General Chemistry
Ch.2 - Atoms & Elements
Ch.3 - Chemical Reactions
BONUS: Lab Techniques and Procedures
BONUS: Mathematical Operations and Functions
Ch.4 - Chemical Quantities & Aqueous Reactions
Ch.5 - Gases
Ch.6 - Thermochemistry
Ch.7 - Quantum Mechanics
Ch.8 - Periodic Properties of the Elements
Ch.9 - Bonding & Molecular Structure
Ch.10 - Molecular Shapes & Valence Bond Theory
Ch.11 - Liquids, Solids & Intermolecular Forces
Ch.12 - Solutions
Ch.13 - Chemical Kinetics
Ch.14 - Chemical Equilibrium
Ch.15 - Acid and Base Equilibrium
Ch.16 - Aqueous Equilibrium
Ch. 17 - Chemical Thermodynamics
Ch.18 - Electrochemistry
Ch.19 - Nuclear Chemistry
Ch.20 - Organic Chemistry
Ch.22 - Chemistry of the Nonmetals
Ch.23 - Transition Metals and Coordination Compounds
Sections
Internal Energy
Calorimetry
Hess's Law
Enthalpy of Formation
End of Chapter 6 Problems
Additional Sections
Units of Energy
Endothermic & Exothermic Reactions

Solution: Researchers at Purdue University have exploited the reactivi...

Problem

Researchers at Purdue University have exploited the reactivity of a reaction to develop a novel type of rocket fuel consisting of aluminum nanoparticles dispersed in H2O(s). They nicknamed this propellant “ALICE” (get it? Al-ice) and noted that in addition to being environmentally friendly, ALICE could be produced on any extraterrestrial body that contains water. The recent discovery of water on Mars could draw new attention to this intriguing fuel. (International Journal of Aerospace Engineering, 2012)

One can speculate that the reaction that causes ALICE to act as a propellant is:

2Al (s) + 3H2O(s) → Al2O3(s) + 3H2(g)  

where the hydrogen gas is subsequently burned. 

A. Given the molar enthalpies for the following reactions, 

2Al(s) + 3/2 O2 (g) → Al2O3 (s)        ΔH° = -1669.8 kJ/mol  

H2 (g) + 1/2 O2 (g) →  H2O (l)         ΔH° =    -285.8 kJ/mol

H2O (s) → H2O (l)                           ΔH° =       6.01 kJ/mol

determine the ΔH° for the ALICE reaction

2Al (s) + 3H2O (s) → Al2O3 (s) + 3H2 (g)

 

 

 

Is the ΔH° you calculated consistent with Al-ice serving as a fuel? ________________

Give one reason to support your answer.